Patent Publication Number: US-2005118258-A1

Title: Pharmaceutical composition comprising skim milk powder

Description:
FIELD OF THE INVENTION  
      The present invention relates to pleasant-tasting compositions made from an unpleasant-tasting therapeutic agent and a taste-masking agent, oral dosage forms of such compositions, methods of making the compositions and methods of treating therewith.  
      Many dosage forms of therapeutic agents are designed to be administered orally. This route of administration is convenient, economical and effective in quickly and easily placing the desired dosage of a therapeutic agent in contact with the relatively large surface membrane of the stomach which has a rich supply of capillaries for passage into the bloodstream. A common disadvantage associated with many such oral dosage forms is the presence of an objectionable or unpleasant taste. The presence of an objectionable or unpleasant taste can affect patient compliance adversely, especially for therapeutic agents in which an extended or frequent course and/or large doses are indicated. Thus, it has been recognized that improving the taste of unpleasant-tasting therapeutic agents can affect patient compliance positively.  
     REPORTED DEVELOPMENTS  
      Compositions have been developed for the purposes of improving the taste of unpleasant-tasting therapeutic agents. For example, British Patent No. 1,257,594 to the Lepetit Group (hereinafter “the &#39;594 patent”) discloses a composition comprising aluminum sodium silicate and powdered milk. The composition is prepared by suspending aluminum sodium silicate and powdered milk in water and then drying the suspension by evaporation in vacuo either by heating the mixture under reduced pressure or by lyophilization. The composition formed in accordance with this process is disclosed as distinctly different from a composition of aluminum sodium silicate and powdered milk formed by dry blending insofar as the dry blended composition is not considered to be effective in masking the unpleasant taste of aluminum sodium silicate.  
      U.S. Pat. No. 5,785,984 to Kurihara et. al. (hereinafter “the &#39;984 patent”) discloses a taste-modifying, bitterness-masking and bitterness-decreasing agent comprising a protein-lipid complex which can be added to a food, pharmaceutical or cosmetic that has a bitter-tasting component. The compositions of the &#39;984 patent are produced by a relatively complicated process in which the protein-lipid complex is itself created in a multi-step process and then combined with a food, pharmaceutical or cosmetic that has a bitter-tasting component.  
     SUMMARY OF THE INVENTION  
      In accordance with the present invention, there is provided a pharmaceutical composition comprising therapeutic agent—generally speaking an unpleasant-tasting one—and skim milk powder. The agent may be any substance or mixture of substances intended for oral administration that has curative, beneficial and/or nutritional value in humans. Typically it has a substantially stable unpleasant taste. The skim milk powder suitable for use may be any commercially available milk powder, or synthetic equivalent thereof, usually having a fat content of less than about 1.25 wt. % and a moisture content of less than about 4 wt. %. The composition of the present invention, preferably in oral dosage form, may further comprise a conventional pharmaceutical excipient. The excipient can serve a number of functions, for example, further enhancing the taste of the composition and/or contributing to the physical properties of oral dosage forms made therefrom.  
      A further aspect of the present invention is a method of making a pharmaceutical composition comprising the step of dry blending such therapeutic agent and skim milk powder in an amount sufficient to mask the (unpleasant) taste of the therapeutic agent. The therapeutic agent and the skim milk powder are combined in a ratio sufficient to provide effective taste-masking of the therapeutic agent, preferably in a ratio of skim milk powder to therapeutic agent of from at least 1:1, typically from about 1:1 to about 1,000,000:1.  
      There are important advantages that stem from the formulation and use of the present invention. The use of skim milk powder is effective in masking the taste of many unpleasant-tasting therapeutic agents. It is also an inexpensive, pharmaceutically acceptable and readily available material that can contribute positively to the physical properties required of many oral dosage forms. Further, compositions of the present invention are able to be formed by conventional and inexpensive production techniques. Such compositions are suitable for use in the formulation of a wide variety of oral dosage forms. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      The composition of the present invention comprises a therapeutic agent and skim milk powder.  
      The term “therapeutic agent” as relevant for the purposes of the present invention includes any substance or mixture of substances intended for oral administration that has curative, beneficial and/or nutritional value in humans and which has a substantially unpleasant taste, either alone or in combination with other substances. The term “unpleasant taste” is defined for present purposes as a taste which gives rise to a statistically significant rating of possessing an objectionable taste when the unmasked form of the therapeutic agent having such taste is provided in a random sampling to a group of humans having an ordinary perception of taste. Examples of such therapeutic agents are set forth in table 1 below.  
                       TABLE 1                       Category   Agent   Typical Dosage Range                  ACE Inhibitor   Enalapril   2.5 mg-20 mg             Captopril   12.5 mg-50 mg             Ramipril   2.5 mg-5 mg         Analgesic   Acetaminophen   100 mg-500 mg        Antidepressant   Imipramine   10 mg-50 mg            Citalopram   20 mg           Fluexitine   10 mg-20 mg        Antihistaminic   Astemizole   5 mg-10 mg           Cetirizine   5 mg-10 mg           Clemastine   1.34 mg-2.68 mg            Ebastine   10 mg           Fexofenadine   30 mg-180 mg           Loratadine   10 mg       Antiulcerative   Famotidine   20 mg-40 mg            Cimetidine   20 mg-800 mg           Omeprazole   10 mg-40 mg        Anti-arrhythmic   Acebutolol   200 mg-400 mg            Amiodarone   100 mg-200 mg            Atenolol   25 mg-100 mg           Carteolol   5 mg-20 mg           Verapamil   120 mg-240 mg        Beta - adrenergic agonist   Albuterol   2 mg-4 mg            Dopexamine   50 mg           Formoterol   6 mg-12 mg       Calcium antagonist   Diltiazem   60 mg-300 mg           Lacidipine   2 mg-4 mg            Nicardipine   20 mg           Nifedipine   5 mg-20 mg           Verapamil   20 mg-400 mg       Corticosteroid   Budesonide   200 mg-400 mg            Dexomethasone   0.5 mg-10 mg             Prednisolone   5 mg-15 mg       COX-2 Inhibitor   Rofecoxib   12.5 mg-25 mg             Celecoxib   100 mg-200 mg        Decongestant   Phenyleprine   1.25 mg-20 mg         Energy promoter   Carnitine   50 mg-500 mg           Ubidecarenone    2 mg-100 mg       Expectorant   Guaifenesin    50 mg-1200 mg       Lipid regulating drug   Lovastatine   10 mg-20 mg        Mineral salt   Boron   20 mg-200 mg           Calcium    50 mg-2000 mg           Chloride   20 mg-100 mg           Chromium   0.02 mg-0.2 mg            Copper   0.6 mg-5 mg             Iodine   20 mg-200 mg           Iron   2 mg-20 mg           Magnesium    10 mg-1000 mg           Manganese   0.6 mg-10 mg             Molybdenum   20 mg-200 mg           Nickel   0.5 mg-20 mg             Potassium    20 mg-1000 mg           Phosphorus    50 mg-1500 mg           Selenium    5 mg-100 mg           Silicon   2 mg-20 mg           Tin    5 mg-100 mg           Vanadium    5 mg-100 mg           Zinc   0.6 mg-100 mg        Mucolytic   Ambroxol   30 mg-60 mg            Carbocisteine   200 mg-275 mg            N-Acetylcysteine    50 mg-1000 mg           Sobrerol   200 mg-300 mg        Natural product   Acerola    5 mg-5000 mg           Ginseng    0.5 mg-5.000 mg           Guaranà    5 mg-500 mg           Lycopene    5 mg-5000 mg       Narcotic   Fentanyl   0.05 mg             Morphine   7.6 mg-75 mg             Methadone    5 mg       Non-Steroidal   Aceclofenac   100 mg        Anti-Inflammatory Drug   Ibuprofen    50 mg-1200 mg           Ketoprofen   25 mg-200 mg           Ketorolac   10 mg           Naproxen   250 mg-500 mg            Nimesulide   50 mg-100 mg       Tranquilizer non narcotic   Buspirone   5 mg-10 mg           Alprazolam   0.5 mg-3 mg             Camazepam   10 mg           Clorazepam   11.25 mg-50 mg              Lorazepam    1 mg-2.5 mg           Nitrazolam    5 mg       Vitamin   Vitamin A    8 mg-1300 mg           Vitamin B 1     0.1 mg-4 mg             Vitamin B 2     0.1 mg-4 mg             Vitamin B 6     0.05 mg-4 mg              Vitamin B 12     0.2 mg-4 mg             Vitamin C    5 mg-2000 mg           Vitamin D 3     0.5 mg-20 mg             Vitamin E   0.5 mg-20 mg             Vitamin K 1     0.5 mg-200 mg            Vitamin PP   1 mg-20 mg           Pantothenic Acid   1 mg-10 mg           Biotin   0.5 mg-100 mg            Folic Acid    30 mg-1000 mg                  
 
 The invention includes within its scope the use of pharmaceutically acceptable salts of any of the foregoing and mixtures of two or more of any of the foregoing. 
 
      Preferred therapeutic agents for use in the composition of the present invention are minerals, vitamins, natural products, antihistaminics, antiuceratives, corticosteroids, antidepressants, mucolytics, expectorants, decongestants, antitussives and analgesics. Particularly preferred therapeutic agents are: calcium; vitamin D 3 ; acerola; vitamins B 1 , B 6 , and PP; acerola; ginseng; guarana; clemastine fumarate; cetirizine; famotidine; prednisolone salts, imipramine, N-acetylcysteine, guaifenesin, phenylephrine, dextromethorpan, acetaminophen, and fexofenadine.  
      The therapeutic agent may include two or more substances having the same or different beneficial properties may be used. For example, the therapeutic agent in a comprise a combination of vitamins, minerals and other dietary supplements in relative proportions suitable for the formation of an oral dosage form that provides substantially all of a person&#39;s daily nutritional needs.  
      The therapeutic agent is included in the composition in an amount sufficient to impart to oral dosage forms made therefrom the desired curative, beneficial and/or nutritional effect. Such amount will vary in accordance with a number of factors including, for example, the particular species of therapeutic agent used, the presence of other ingredients, the specific type of oral dosage formulation employed, and the particular application in which the composition is intended to be used. It is believed that in most applications, the amount of therapeutic agent included in the composition will be from about 0.01 wt. % to about 50.00 wt. %. In preferred form, the amount of therapeutic agent included in the composition will be from about 0.05 wt. % to about 30.00 wt. %, and even more preferably from about 0.09 wt. % to about 8.33 wt. %.  
      The use of the present invention is particularly effective with a therapeutic agent where unpleasant taste is substantially stable over time, that is, the degree of unpleasantness does not intensify due to chemical changes in the therapeutic agent, for example, through hydrolysis, oxidization, or degradation, of one or more constituents comprising the agent. An example of a therapeutic agent with an unpleasant taste that is not substantially stable over time is acetylsalicylic acid (ASA). In the presence of moisture, ASA is known to hydrolyze into acetic and salicylic acids. The presence of acetic acid resulting from hydrolysis can increase substantially the unpleasant taste of ASA. As a consequence, an amount of skim milk powder which is effective in masking the taste of unhydrolyzed ASA may be rendered less effective or even ineffective in masking the taste of ASA which has hydrolyzed.  
      As set forth above, the term “skim milk powder” is defined for present purposes as the solids component of skim milk in powder form with no more than about 4% moisture content and no more than about 1.25% fat content. Skim milk powder is made commonly by spray drying liquid-skim milk and comprises typically from about 34% to about 37% protein; from about 49% to about 52% carbohydrate; from about 8% to about 9% ash; minerals, for example, calcium, sodium, potassium, phosphorus, iron, magnesium and zinc; and amino acids, for example, isoleucine, leucine, lysine, methionine and phenylalanine. It is further considered within the scope of the present invention to use in place of or in combination with the skim milk powder a synthetic mixture of some or all of the components found in skim milk powder (e.g. those identified above preferably including milk protein(s)).  
      The skim milk powder is included in the composition in an amount at least sufficient to mask the taste of the unpleasant-tasting therapeutic agent. An amount of skim milk powder in excess of the amount required to mask the taste of the unpleasant-tasting therapeutic agent may be desired in applications in which other desired properties are sought. The amount of skim milk powder will vary in accordance with a number of factors including, for example, the particular species of therapeutic agent used, the presence of other ingredients, the specific type of the oral dosage formulation, and the particular application in which the composition is intended to be used. It is believed that for most applications, the ratio of skim milk powder to therapeutic agent will be from about 1:1 to about 1,000,000:1. In preferred form, the ratio will be from about 1:1 to about 1,000:1, and even more preferably from about 1:1 to about 100:1. (These are generally weight ratios).  
      While not intending to be bound by any particular theory, it is believed that the proteins in the skim milk powder act to mask the taste of the therapeutic agent by blocking the taste receptors located on the tongue. This blocking action may occur either by preferential binding of the proteins to receptor sites, by formation of a film over the receptor site which acts as a physical barrier to the therapeutic agent, or by some other mechanism. The carbohydrates and sugars present in skim milk powder enhance the palatability of the compositions and contribute to the physical characteristics of the composition.  
      The composition of the present invention may include also conventional excipients of the type used in pharmaceutical compositions. Examples of suitable excipients include: diluents, binders, disintegrants, surfactants, hydrophilic polymers, film-coating polymers, lubricants, glidants (or anti-adherents), plasticizers, pH modifiers, preservatives, coloring, flavoring and/or aromatic substances.  
      There are applications in which the selected therapeutic agent is administered in small doses. In such applications, diluents are used to increase the volume occupied by a unit dose of the therapeutic agent so that the oral dosage form containing the therapeutic agent does not have inconveniently small dimensions. Diluents are selected in such applications so as to not inhibit the bioavailability of the therapeutic agent or impair the mechanical characteristics of the oral dosage form that is used. Examples of suitable diluents include microcrystalline cellulose; lactose, sucrose, fructose, glucose, dextrose, or other sugars; dibasic calcium phosphate; calcium sulfate; cellulose; ethylcellulose; cellulose derivatives; kaolin; mannitol, lactitol, maltitol, xylitol, sorbitol, or other sugar alcohols; dry starch; dextrin, maltodextrin or other polysaccharides; inositol; or mixtures thereof.  
      A binder may be used in the composition of the present invention to improve the physical properties of a oral dosage forms such as tablets made therefrom. In those applications in which the therapeutic agent has low bioavailability, a relatively large quantity of the therapeutic agent is required in each unit dose. When the therapeutic agent also exhibits poor pressability (the ability to be pressed into tablet form), such compositions yield oral dosage forms which have low strength and are unacceptably friable. The addition of a binder material to such compositions imparts cohesiveness to the composition and improves its physical properties. Examples of suitable binders include starches, hydroxypropylmethyl cellulose, hydroxypropyl cellulose, ethyl cellulose, polyvinyl pyrrolidone, acacia, guar gum, hydroxyethylcellulose, agar, calcium carrageenan, sodium alginate, gelatin, saccharides (including glucose, sucrose, dextrose and lactose), molasses, extract of Irish moss, panwar gum, ghatti gum, mucilage of isapol husk, carboxymethylcellulose, methylcellulose, veegum, larch arbolactan, polyethylene glycols, waxes and mixtures thereof.  
      A disintegrant may be used in the composition of the present invention to promote rapid decomposition of an oral dosage form thereof following administration. Rapid decomposition of the oral dosage form insures that the therapeutic agent is released quickly following administration. By providing a component in an oral dosage form which is readily soluble in the oral cavity, the oral dosage form is readily disintegrated when administered. Examples of suitable disintegrants include starches, sodium starch glycolate, crospovidone, croscarmellose, microcrystalline cellulose, low substituted hydroxypropyl cellulose, pectins, potassium methacrylate-divinylbenzene copolymer, polyvinyl alcohol, thylamide, sodium bicarbonate, sodium carbonate, starch derivatives, dextrin, beta cyclodextrin, dextrin derivatives, magnesium oxide, clays, bentonite and mixtures thereof.  
      A surfactant may be used in the composition of the present invention to disperse the therapeutic agent at the situs of release. Examples of suitable surfactants include nonionic surfactants, for example, sorbitan sesquioleate, polyoxyethylene sorbitan monooleate, polyoxyethylene monostearate, glycerol monostearate, propylene glycol monolaurate, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether or polyoxyethylene hydrogenated castor oil, and ionic surfactants such as sodium dodecyl sulfate or benzalkonium chloride.  
      Examples of suitable hydrophilic polymers include hydroxypropylmethyl cellulose; carbomers; polyethylene oxides; hydroxypropyl cellulose; hydroxyethyl cellulose; carboxymethylcellulose; sodium carboxymethylcellulose; carboxyvinyl polymers; polyvinyl alcohol; glucans; scleroglucans; mannans; xanthans; carboxymethylcellulose and its derivatives; methylcellulose; cellulose; crosslinked polyvinylpyrrolidone; carboxymethyl starch; potassium methacrylate-divinylbenzene copolymer; hydroxypropylcyclodextrin; alpha, beta, gamma cyclodextrin or derivatives and other dextran derivatives; natural gums; seaweed extract; plant exudate; agar; agarose; algin; sodium alginate; potassium alginate; carrageenan; kappa-carrageenan; lambda-carrageenan; fucoidan, furcellaran; laminarin; hypnea; eucheuma; gum arabic; gum ghatti; gum karaya; gum tragacanth; guar gum; locust bean gum; quince psyllium; flax seed; okra gum; arabinogalactin; pectin; scleroglucan; dextran; amylose; amylopectin; dextrin; acacia; karaya; guar; a swellable mixture of agar and carboxymethyl cellulose; a swellable composition comprising methyl cellulose mixed with a sparingly cross-linked agar; a blend of sodium alginate; and locust bean gum.  
      Examples of suitable film-coating polymers include enteric polymer coating materials, such as, for example, cellulose acetate phthalate, cellulose acetate trimaletate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, Eudragit® poly acrylic acid and poly acrylate and methacrylate coatings, polyvinyl acetaldiethylamino acetate, hydroxypropyl methylcellulose acetate succinate, cellulose acetate trimellitate, shellac; hydrogels and gel-forming materials, such as, for example, carboxyvinyl polymers, sodium alginate, sodium carmellose, calcium carmellose, sodium carboxymethyl starch, polyvinyl alcohol, hydroxyethyl cellulose, methyl cellulose, gelatin, starch and cellulose-based cross-linked polymers, hydroxypropyl cellulose, hydroxypropyl methylcellulose, polyvinylpyrrolidone, crosslinked starch, microcrystalline cellulose, chitin, cellulose acetate, cellulose proprionate, cellulose acetate propionate, cellulose acetate butyrate, cellulose triacetate, aminoacryl-methacrylate copolymer (Eudragit® RS-PM, Rohm &amp; Haas), pullulan, collagen, casein, agar, gum arabic, sodium carboxymethyl cellulose, carboxymethyl ethyl cellulose, swellable hydrophilic polymers, poly(hydroxyalkyl methacrylate) (m. wt. ˜5 k-5,000 k), polyvinylpyrrolidone (m. wt. ˜10k-360 k), anionic and cationic hydrogels, polyvinyl alcohol having a low acetate residual, a swellable mixture of agar and carboxymethyl cellulose, copolymers of maleic anhydride and styrene, ethylene, propylene or isobutylene, pectin (m. wt. ˜30 k-300 k), polysaccharides such as agar, acacia, karaya, tragacanth, algins and guar, polyacrylamides, Polyox® polyethylene oxides (m. wt. ˜100 k-5,000 k), AquaKeep® acrylate polymers, diesters of polyglucan, crosslinked polyvinyl alcohol and poly N-vinyl-2-pyrrolidone, sodium starch glycollate (e.g. Explotab®; Edward Mandell C. Ltd.); hydrophilic polymers such as polysaccharides, methyl cellulose, sodium or calcium carboxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose, nitro cellulose, carboxymethyl cellulose, cellulose ethers, poly(ethylene terphthalate), poly(vinyl isobutyl ether), polyurethane, polyethylene oxides (e.g. Polyox®, Union Carbide), methyl ethyl cellulose, ethylhydroxy ethylcellulose, cellulose acetate, ethylcellulose, cellulose butyrate, cellulose propionate, gelatin, collagen, starch, maltodextrin, pullulan, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl acetate, glycerol fatty acid esters, polyacrylamide, polyacrylic acid, copolymers of methacrylic acid or methacrylic acid (e.g. Eudragit®, Rohm and Haas), other acrylic acid derivatives, ethyl acrylate-methyl methacrylate copolymer, sorbitan esters, polydimethyl siloxane, natural gums, lecithins, pectin, alginates, ammonia alginate, sodium, calcium, potassium alginates, propylene glycol alginate, agar, gums: arabic, karaya, locust bean, tragacanth, carrageenan, guar, xanthans, scleroglucan and mixtures and blends thereof.  
      A lubricant may be used in the composition of the present invention to facilitate manufacturing of oral dosage forms made therefrom. In applications in which the composition is tableted, a lubricant is included in the composition so that the pressed tablet will slide from the die in which it is pressed without mechanical damage to the tablet. Lubricants can also effect the manner in which individual components of a powder slide when pressed into tablets, reducing the formation of voids within a tablet, thereby reducing tablet to tablet weight variation due to void formation. Examples of suitable lubricants include stearic acid, magnesium stearate, talc, calcium stearate, hydrogenated vegetable oils, sodium benzoate, sodium chloride, leucine, magnesium lauryl sulfate, colloidal silicon dioxide, glyceryl mono stearate, waxes, hydrogenated oils, and polyethylene glycol.  
      Examples of suitable gliants (or anti-adherents) include colloidal silica, fumed silicon dioxide, silica hydrogels, talc, fumed silica, gypsum, kaolin, glycerol monostearate and magnesium stearate.  
      Suitable plasticizers include acetylated monoglycerides, butyl phthalyl butyl glycolate, dibutyl tartrate, diethyl phthalate, dimethyl phthalate, ethyl phthalyl ethyl glycolate, glycerin; propylene glycol, triacetin, citrate, tripropioin, diacetin, dibutyl phthalate, acetyl monoglyceride, polyethylene glycols, castor oil, triethyl citrate, polyhydric alcohols, glycerol, acetate esters, gylcerol triacetate, acetyl triethyl citrate, dibenzyl phthalate, dihexyl phthalate, butyl octyl phthalate, diisononyl phthalate, butyl octyl phthalate, dioctyl azelate, epoxidised tallate, triisoctyl trimellitate, diethylhexyl phthalate, di-n-octyl phthalate, di-i-octyl phthalate, di-i-decyl phthalate, di-n-undecyl phthalate, di-n-tridecyl phthalate, tri-2-ethylhexyl trimellitate, di-2-ethylhexyl adipate, di-2-ethylhexyl sebacate, di-2-ethylhexyl azelate, dibutyl sebacate, glyceryl monocaprylate, glyceryl monocaprate.  
      Examples of suitable pH modifiers include organic acids such as citric acid, fumaric acid, tartaric acid, succinic acid, ascorbic acid, malic acid, glutaric acid, adipic acid, lactic acid, fumaric acid, salts of these acids; salts of inorganic acids and magnesium hydroxide; sodium, potassium, calcium and magnesium salts of carbonate, bicarbonate, citrate and phosphate; and amino acids such as arginine, glycine and lysine.  
      Flavoring agents may be used in the compositions of the present invention to make oral dosage forms made therefrom more palatable than they would be in the absence of such flavoring agents. Unflavored oral dosage forms tend to be perceived as gritty or chalky in the absence of such flavoring agents. Flavoring agents play no essential part in the performance of the skim milk powder in masking the unpleasant taste of the therapeutic agent and, in fact, are ineffective by themselves in rendering palatable therapeutic agents which have an objectionable taste in the absence of skim milk powder. Suitable flavoring agents may provide sweetness, and/or a particular flavor, and include honey flavor, banana flavor, wild berry flavor, glycyrrhiza (licorice) flavor, chocolate flavor, vanilla flavor caramel flavor, and various forms of sugar.  
      The excipient is included in the composition in an amount sufficient to impart or enhance the physical and/or organoleptic properties of oral dosage formulations made therefrom. The amount of excipient will vary in accordance with a number of factors including, for example, the particular species of therapeutic agent used, the amount of skim milk powder used, the presence of other ingredients, the specific type of oral dosage formulation, and the particular application in which the composition is intended to be used. It is believed that for most applications, the amount of excipient included in the composition will be from about 0.1 to about 99 wt. %. In preferred embodiments, the amount of excipient included in the composition will be from about 0.2 wt. % to about 90 wt. %, and even more preferably from about 0.3 wt. % to about 70 wt. %.  
      Flowability refers to the ability of a bulk powder to fill a mold (as for pressing into a tablet). It is expressed as the tendency of a fixed volume of a powder to spread (rather than to form a conical shaped mound) when poured onto a flat surface under controlled conditions and is measured in units of degrees of angle of the conical mound with respect to the surface on which it sits. In preferred form, the composition of the present invention will have a flowability as measured by an angle of repose between about 30 to about 45.  
      Density is defined in the conventional sense of mass/unit volume. The bulk density of a powder composition includes the interparticulate void volume. As a result, the bulk density of a powder composition depends on both the density of the powder particles and the spatial arrangement of particles in the powder volume. In measuring the density of powders, bulk density is determined by measuring the volume of a known mass of powder that has been passed through a screen into a graduated cylinder. Tapped density is determined after a standard compacting vibration has been applied to the volumetric vessel. Lower density powders tend to be more easily pressed into cohesive tablets than high density powders, and low density powders tend to achieve cohesiveness at lower pressing pressure, and therefore generally also yield lower density tablets. In preferred form, the composition of the present invention has a bulk density of from about 0.4 to about 0.9 g/ml and a tapped density of from about 0.5 to about 1.1 g/ml.  
      The composition of the present invention for oral use can be in any form suitable for the oral administration of a therapeutic agent. For example, the oral dosage formulation may be in the form of a chewable tablet, swallowable tablet, effervescent tablet, fast melt tablet, multiparticulate capsule, dry syrup, powder, sprinkle, or sachet. In preferred embodiments, the oral dosage formulation is in the form of a chewable tablet or a fast melt tablet. In such embodiments, the tablet may be uncoated or it may be coated by known techniques for a variety of purposes including, for example, protection of the composition, or improving the aesthetics of the tablet.  
      Tablets can be characterized by homogeneity, hardness, friability, speed of disintegration, and speed of dispersibility of the therapeutic agent contained therein. Homogeneity refers to the variability of the amount of therapeutic agent contained in random samples of the bulk powder or dosage forms. Defined in terms of stated dose, it is preferred that any one sample of an oral dosage form of the present invention contain between about 85% and about 115% of the stated dose of the therapeutic agent. A 10 unit sampling of an oral dosage form of the present invention, when averaged, will provide preferably between about 95% and about 105% of the stated dose of the therapeutic agent.  
      Tablet hardness is expressed as the amount of force that must be applied for a tablet to break. One method of measuring tablet hardness employs an apparatus known as a Schleuniger tablet hardness tester. According to this method, a force is applied perpendicular to the edge of the tablet and directed across the diameter of the tablet under test until the tablet fractures. In preferred embodiments of the present invention in which the oral dosage form is a chewable tablet, the tablet has a hardness, as measured by a Schleuniger tablet hardness tester, of from about 0.5 Kp to about 30 Kp and more preferably from about 1 Kp to about 20 Kp. In preferred embodiments of the present invention in which the oral dosage form is a fast melt tablet, the tablet has a hardness, as measured by a Schleuniger tablet hardness tester, of from about 0.5 Kp to about 10 Kp and more preferably from about 1 Kp to about 10 Kp. In preferred embodiments of the present invention in which the oral dosage form is an effervescent tablet, the tablet has a hardness, as measured by a Schleuniger tablet hardness tester, of from about 1 Kp to about 25 Kp and more preferably from about 3 Kp to about 20 Kp.  
      Friability is measured by tumbling a standard sampling of tablets in a standard apparatus at a standard speed for a standard time and measuring the weight loss of the tablets due to material being ablated from the tablets. In preferred embodiments of the present invention in which the oral dosage form is a tablet, the tablet has a friability of from about 0.1% to about 3%, and more preferably from about 0.2% to about 1%.  
      Disintegration time is measured by placing the tablet in a standard gastric solution held at a given temperature with a standard amount of agitation. The time recorded is the time elapsed from contact with the solution until the tablet falls into pieces small enough to pass through a standard screen. In preferred embodiments of the present invention in which the oral dosage form is a non-effervescent tablet, the tablet has a disintegration time of from about 10 seconds to about 30 minutes and more preferably from about 30 seconds to about 15 minutes. In preferred embodiments of the oral dosage form of the present invention in which the oral dosage form is in the form of an effervescent tablet, the tablet will have a disintegration time from about 10 seconds to about 5 minutes, and more preferably from about 30 to about 3 minutes.  
      The composition of the present invention can be made in any suitable way, for example by dry blending the therapeutic agent and skim milk powder and optional ingredients to homogeneity. The dry blended composition is suitable for use in forming the oral dosage formulations of the present invention and, upon ingestion, will mask effectively the unpleasant taste of the therapeutic agent.  
     EXAMPLES  
      The following compositions are illustrative of the taste-masking effect of the present invention as applied to a variety of therapeutic agents which are recognized as having an unpleasant taste. The various sugars, sweeteners, and flavoring agents employed in the compositions described below are insufficient on their own to eliminate the unpleasant taste of the therapeutic agents with which they are combined, but serve only to enhance further the taste of the resulting composition and/or the physical properties of the oral dosage forms made therefrom.  
      The oral dosage forms described in Example Nos. 1 to 21 set forth below were evaluated for their taste. The taste test was designed to elicit subjective evaluations of taste with respect to various flavor characteristics such as sweet, salty, sour, bitter, warm, cool, burning, irritating, anesthetic, and aftertaste. A group of volunteer tasters were provided a series of samples and asked to rate each sample on a scale from 1 (lowest) to 5 (highest) for each taste characteristic. The samples that were provided comprised both unmasked therapeutic agents as well as oral dosage formulations in accordance with the present invention that included such therapeutic agents in combination with skim milk powder. The data collected from the volunteers (set out in tabular form in and found to provide a statistically significant change in taste ratings when comparing the unmasked therapeutic agent to the therapeutic agent as part of oral dosage formulations made in accordance with the present invention.  
      For Example Nos. 1 through 11, the ingredients were blended mechanically for 15 minutes at room temperature in a cube mixer. The resulting mixtures were tableted by a single punch tableting machine using a plane punch of 18 mm in diameter.  
     Example No. 1  
      In this example, the unpleasant chalky taste associated with calcium phosphate dibasic has been is eliminated effectively by the inclusion of skim milk powder in the tablet described below.  
                                                      calcium phosphate dibasic   3.90 g           skim milk powder   135.55 g            sorbitol   108.70 g            honey flavor   0.76 g           banana flavor   1.09 g           magnesium stearate   0.76 g                      
 
      The tablets produced in this example had a thickness of approximately 7.7 mm and a hardness of 23 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.3 g each, contained 10.6 mg of calcium and 8.1 mg of phosphorous per tablet, and had a pleasant and sweet taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   Unpleasent                                                                                    Therapeutic   %   24   20   20   28   20   20   20   20   60   28   60       agent alone   1-5   1.2   1   1   1.4   1   1   1   1   3   1.4   3       Tablet of   %   20   56   20   52   20   20   20   20   20   80   20       Example   1-5   1   2.8   1   2.6   1   1   1   1   1   4   1       No. 1                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant taste and an aftertaste due to a heartily chalky sensation.            Tablet of Example No. 1 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 2  
      In this example, the taste-masking effect is demonstrated in a tablet that includes two therapeutic agents, namely, calcium phosphate dibasic and vitamin D 3  which is known to have a strong and unpleasant vitamin taste.  
                                                      calcium phosphate dibasic   3.12 g           vitamin D 3     0.17 g           skim milk powder   109.14 g            dextrose   86.96 g            magnesium stearate   0.61 g                      
 
      The tablets produced in this example had a thickness of approximately 7.8 mm and a hardness of 11 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.3 g each, contained 10.6 mg of calcium, 8.1 mg of phosphorus, and 5 μg of vitamin D 3  per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   Pleasant   unpleasant                                                                                    Therapeutic   %   76   20   20   40   20   36   40   20   76   24   68       agents alone   1-5   3.8   1   1   2   1   1.8   2   1   3.8   1.2   3.4       Tablet of   %   20   52   20   56   20   20   20   20   20   76   20       Example   1-5   1   2.6   1   2.8   1   1   1   1   1   3.8   1       No. 2                 Comment            Therapeutic agents alone The therapeutic agents have an unpleasant taste and an aftertaste due to a heartily chalky sensation. Vitamin D 3  in particular shows a very bitter taste and aftertaste.            Tablet of Example No. 2 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 3  
      In this example, the taste-masking effect is demonstrated by a tablet that includes calcium phosphate dibasic and acerola which is an excellent source of vitamin C and is recognized as having an unpleasant acidic taste.  
                                                      calcium phosphate dibasic   3.90 g           acerola   38.37 g            skim milk powder   97.18 g            fructose   108.70 g            wild berry flavor   1.09 g           magnesium stearate   0.76 g                      
 
      The tablets produced in this example had a thickness of approximately 7.5 mm and a hardness of 27 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.3 g each, contained 10.6 mg of calcium, 8.1 mg of phosphorus, and 60 mg of vitamin C per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   40   20   20   20   20   20   20   20   52   20   52       agents alone   1-5   2   1   1   1   1   1   1   1   2.6   1   2.6       Tablet of   %   20   60   20   24   24   20   20   20   20   64   20       Example   1-5   1   3   1   1.2   1.2   1   1   1   1   3.2   1       No. 3                 Comment            Therapeutic agents alone The therapeutic agents have an unpleasant bitter and acid persistent taste.            Tablet of Example No. 3 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 4  
      This example demonstrates the taste-masking effect in a tablet that includes a combination of vitamins each of which is known to have a strong and unpleasant vitamin taste.  
                                                      vitamin B 1  mononitrate   0.07 g           vitamin B 6     0.09 g           vitamin PP   0.82 g           skim milk powder   57.80 g            fructose   40.90 g            magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.7 mm and a hardness of 20 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.3 g each, contained 1.50 mg of vitamin B 1 , 2.00 mg of vitamin B 6  and 18.00 mg of vitamin PP per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Vitamin   %   64   20   28   20   20   36   20   20   64   24   68       B 1  alone   1-5   3.2   1   1.4   1   1   1.8   1   1   3.2   1.2   3.4       Vitamin   %   64   20   40   20   20   20   20   20   68   28   72       B 6  alone   1-5   3.2   1   2   1   1   1   1   1   3.4   1.4   3.6       Vitamin   %   72   20   40   20   20   24   20   20   72   24   72       PP alone   1-5   3.8   1   2   1   1   1.2   1   1   3.6   1.2   3.6       Tablet of   %   20   44   24   40   20   20   20   20   20   56   20       Example   1-5   1   2.2   1.2   2   1   1   1   1   1   2.8   1       # 4                 Comment            Therapeutic agents alone The therapeutic agents have an unpleasant bitter taste and aftertaste.            Tablet of Example No. 4 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 5  
      This example demonstrates the taste-masking effect in a tablet that includes ginseng extract which is known to have an unpleasant bitter taste.  
                                                      ginseng extract   4.55 g           skim milk powder   54.00 g            sorbitol   40.90 g            glycirriza flavor   0.23 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 22 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.2 g each, contained 100.00 mg of ginseng extract per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   60   20   20   24   20   20   20   20   64   28   60       agent alone   1-5   3   1   1   1.2   1   1   1   1   3.2   1.4   3       Tablet of   %   20   44   20   32   44   20   20   20   48   68   20       Example   1-5   1   2.2   1   1.6   2.2   1   1   1   2.4   3.4   1       No. 5                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant bitter taste and aftertaste.            Tablet of Example No. 5 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 6  
      This example demonstrates the taste-masking effect in a tablet that includes guarana extract, another therapeutic agent which is known to have an unpleasant bitter taste.  
                                                      guarana extract   2.27 g           skim milk powder   56.05 g            dextrose   40.90 g            white chocolate flavor   0.46 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 23 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.2 g each, contained 50.00 mg of guarana extract per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   52   20   20   24   20   20   20   20   36   28   64       agent alone   1-5   2.6   1   1   1.2   1   1   1   1   1.8   1.4   3.2       Tablet of   %   20   44   20   24   44   20   20   20   44   60   20       Example   1-5   1   2.2   1   1.2   2.2   1   1   1   2.2   3   1       No. 6                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant bitter taste and aftertaste.            Tablet of Example No. 6 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 7  
      This example demonstrates the taste-masking effect in a tablet that includes clemastine fumarate, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      clemastine fumarate   0.09 g           skim milk powder   58.23 g            sorbitol   40.90 g            white chocolate flavor   0.46 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 25 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.2 g each, contained 2.00 mg of clemastine fumarate per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   84   20   20   24   20   26   24   36   72   24   72       agent alone   1-5   4.2   1   1   1.2   1   1.2   1.2   1.8   3.6   1.2   3.6       Tablet of   %   20   40   20   40   24   20   20   20   20   52   24       Example   1-5   1   2   1   2   1.2   1   1   1   1   2.6   1.2       No. 7                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant bitter taste and aftertaste.            Tablet of Example No. 7 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 8  
      This example demonstrates the taste-masking effect in a tablet that includes cetirizine di-HCl, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      cetirizine di-HCl   0.45 g           skim milk powder   57.87 g            dextrose   40.90 g            white chocolate flavor   0.46 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 18 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 2.2 g. each, contained 10.00 mg. of cetirizine di-HCl per tablet, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       testers: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   60   20   24   28   36   32   20   28   52   24   60       agent alone   1-5   3   1   1.2   1.4   1.8   1.6   1   1.4   2.6   1.2   3       Tablet of   %   24   40   20   40   20   20   20   20   24   60   24       Example   1-5   1.2   2   1   2   1   1   1   1   1.2   3   1.2       No. 8                 Comment            Therapeutic agent alone Therapeutic agent shows a bitter taste and aftertaste, accompanied by a light burning and anesthetic sensations.            Tablet of Example No. 8 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 9  
      This example demonstrates the taste-masking effect in a tablet that includes famotidine, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      famotidine   0.91 g           skim milk powder   57.41 g            saccharose   40.90 g            white chocolate flavor   0.46 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 18 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.2 g each, contained 20.00 mg of famotidine, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       volunteers: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   64   20   20   20   20   24   20   20   48   28   56       agent alone   1-5   3.2   1   1   1   1   1.2   1   1   2.4   1.4   2.8       Tablet of   %   24   44   20   40   20   20   20   20   24   60   24       Example   1-5   1.2   2.2   1   2   1   1   1   1   1.2   3   1.2       No. 9                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant persistent bitter taste and aftertaste.            Tablet of Example No. 9 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 10  
      This example demonstrates the taste-masking effect in a tablet that includes prednisolone sodium phosphate, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      prednisolone sodium phosphate   2.73 g           skim milk powder   55.82 g            fructose   40.90 g            glycyrrhiza flavor   0.23 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 20 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.2 g each, contained 60.00 mg of prednisolone sodium phosphate, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasant                                                                                    Therapeutic   %   60   20   40   20   24   20   20   20   36   28   52       agent alone   1-5   3   1   2   1   1.2   1   1   1   1.8   1.4   2.6       Tablet of   %   20   48   20   40   20   20   20   20   20   60   20       Example   1-5   1   2.4   1   2   1   1   1   1   1   3   1       No. 10                 Comment            Therapeutic agent alone The therapeutic agent has a bitter and light salty taste.            Tablet of Example No. 10 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 11  
      This example demonstrates the taste-masking effect in a tablet that includes imipramine HCl, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      imipramine HCl   1.14 g           skim milk powder   57.41 g            fructose   40.90 g            glycyrrhiza flavor   0.23 g           magnesium stearate   0.32 g                      
 
      The tablets produced in this example had a thickness of approximately 7.4 mm and a hardness of 23 Kp as measured by a Schleuniger tablet hardness tester, weighed 2.2 g each, contained 25.00 mg of imipramine HCl, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   60   20   20   20   40   56   36   72   68   28   72       agent alone   1-5   3   1   1   1   2   2.8   1.8   3.8   3.4   1.4   3.6       Tablet of   %   20   44   20   40   24   20   20   32   32   52   24       Example   1-5   1   2.2   1   2   1.2   1   1   1.6   1.6   2.6   1.2       No. 11                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant bitter taste and aftertaste. Burning and anesthetic sensation is very evident.            Tablet of Example No. 11 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 12  
      This example demonstrates the taste-masking effect in a tablet that includes vitamin PP, a therapeutic agent which is known to have an unpleasant taste.  
                                                      vitamin PP   15.00 g            skim milk powder   213.33 g            aspartame   6.67 g           vanilla flavor   8.34 g           magnesium stearate   6.67 g                      
 
      The above ingredients were blended mechanically for 15 minutes at room temperature in a cube mixer. The resulting mixture was tableted by a single punch tableting machine using a plane punch of 12 mm in diameter to yield tablets with a thickness of approximately 3 mm and a hardness of 7.5 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 300 mg each, contained 18.00 mg of vitamin PP, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Vitamin   %   72   20   40   20   20   24   20   20   72   24   72       PP alone   1-5   3.8   1   2   1   1   1.2   1   1   3.6   1.2   3.6       Tablet of   %   24   44   20   40   24   20   20   20   24   60   24       Example   1-5   1.2   2.2   1   2   1.2   1   1   1   1.2   3   1.2       No. 12                 Comment            Therapeutic agent alone The therapeutic agent has an unpleasant bitter taste and aftertaste.            Tablet of Example No. 12 A sweet sensation is obtained in the oralcavity. Tablets have a pleasant taste.             
 
     Example No. 13  
      This example demonstrates the taste-masking effect in a tablet that includes N-acetylcysteine, a pharmaceutical agent which is known to have an unpleasant taste.  
                                                      N-acetylcysteine     1 g           skim milk powder   98.70 g            honey flavor   0.1 g           polyvinylpyrrolidone   0.2 g                      
 
      The N-acetylcysteine and skim milk powder were placed in an Aeromatic Strea 1 fluidized bed coating apparatus and granulated with an aqueous solution of the polyvinylpyrrolidone in 30 ml water. The mixture was dried for about 30 minutes at 50C and then cooled. The honey flavor was added to the granules and the resulting mixture was blended for 15 minutes to reach homogeneity. The mixture was packaged in sachets of 20 g each to obtain a single dosage form of 200 mg of N-acetylcysteine for use in a 2 deciliter aqueous solution. The resulting solution had a pleasant taste in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   40   20   48   20   20   20   40   20   52   32   60       agent alone   1-5   2   1   2.4   1   1   1   2   1   2.6   1.6   3       Oral dosage   %   20   60   20   40   20   20   20   20   20   72   20       form of   1-5   1   3   1   2   1   1   1   1   1   3.8   1       Example       No. 13                 Comment            Therapeutic agent alone N-Acetylcysteine shows a sulfuric typical taste and after taste.            Oral dosage form of Example No. 13 A sweet sensation is obtained in the oral cavity, when the milk is added. Tablets have a pleasant taste.             
 
     Example No. 14  
      This example demonstrates the taste-masking effect in a chewable tablet that includes prednisolone sodium phosphate, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      prednisolone sodium phosphate   13.44 g            skim milk powder   370.56 g            chocolate flavor   14.0 g           polyethylene glycol   20.0 g           sorbitol   80.0 g           xylitol   40.0 g           mannitol   130.0 g            citric acid    6.0 g           aspartame   16.0 g           magnesium stearate   10.0 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were placed in an Aeromatic Strea 1 fluidized bed coating apparatus and granulated with an aqueous solution containing polyethylene glycol in 50 ml of demineralized water. The granules were dried for about 40 minutes at about 55C and then cooled. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 12 mm in diameter to yield tablets with a thickness of approximately 4 mm and a hardness of about 1 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 350 mg each, contained 6.72 mg of prednisolone sodium phosphate, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   60   20   40   20   24   20   20   20   36   28   52       agent alone   1-5   3   1   2   1   1.2   1   1   1   1.8   1.4   2.6       Tablet of   %   20   56   20   36   20   20   20   20   20   48   20       Example   1-5   1   2.8   1   1.8   1   1   1   1   1   2.4   1       No. 14                 Comment            Therapeutic agent alone The therapeutic agent has a bitter and light salty taste.            Tablet of Example No. 14 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 15  
      This example demonstrates the taste-masking effect in a chewable tablet that includes guaifenesin, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      guaifenesin   10.0 g           skim milk powder   59.3 g           chocolate flavor   2.25 g           polyethylene glycol    3.2 g           sorbitol   12.88 g            xylitol   6.41 g           mannitol   20.83 g            citric acid   0.96 g           aspartame   2.57 g           magnesium stearate    1.6 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 14. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 16 mm in diameter to yield tablets with a thickness of approximately 7 mm and a hardness of about 1.5 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 1.2 g each, contained 100 mg of guaifenesin, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   72   20   40   20   20   36   20   20   80   20   80       agent alone   1-5   3.6   1   2   1   1   1.8   1   1   4   1   4       Tablet of   %   28   48   20   40   20   20   20   20   36   48   28       Example   1-5   1.4   2.4   1   2   1   1   1   1   1.8   2.4   1.4       No. 15                 Comment            Therapeutic agent alone Guaifenesin shows a very bitter taste and aftertaste persistent and nauseating.            Tablet of Example No. 15 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 16  
      This example demonstrates the taste-masking effect in a chewable tablet that includes guaifenesin and phenylephrine HCl, pharmaceutical agents which are known to have an unpleasant bitter taste.  
                                                      guaifenesin   10.0 g           phenylephrine HCl   0.25 g           skim milk powder   59.05 g            chocolate flavor   2.25 g           polyethylene glycol    3.2 g           sorbitol   12.88 g            xylitol   6.41 g           mannitol   20.83 g            citric acid   0.96 g           aspartame   2.57 g           magnesium stearate    1.6 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 14. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 16 mm in diameter to yield tablets with a thickness of approximately 7 mm and a hardness of about 1.5 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 1.2 g each, contained 100 mg of guaifenesin and 2.5 mg of phenylephrine HCl and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   52   20   40   20   20   20   20   20   44   28   64       agent alone   1-5   2.6   1   2   1   1   1   1   1   2.2   1.4   3.2       Tablet of   %   44   28   24   28   20   20   20   20   44   44   44       Example   1-5   2.2   1.4   1.2   1.4   1   1   1   1   2.2   2.2   2.2       No. 16                 Comment            Therapeutic agent alone Therapeutic agents show a unpleasant bitter taste.            Tablet of Example No. 16 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 17  
      This example demonstrates the taste-masking effect in a fast melt tablet that includes guaifenesin and dextromethorphan HBr pharmaceutical agents which are known to have an unpleasant bitter taste.  
                                                      guaifenesin   10.0 g           dextromethorphan HBr    0.5 g           skim milk powder   37.25 g            chocolate flavor   2.25 g           polyethylene glycol   4.62 g           sorbitol   18.61 g            xylitol   9.26 g           mannitol   30.10 g            citric acid   1.39 g           aspartame   3.71 g           magnesium stearate   2.31 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 14. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 16 mm in diameter to yield tablets with a thickness of approximately 7 mm and a hardness of about 2 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 1.2 g each, contained 100 mg of guaifenesin and 5 mg of dextromethorphan HBr, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   84   20   20   20   20   40   36   20   72   24   76       agents alone   1-5   4.2   1   1   1   1   2   1.8   1   3.6   1.2   3.8       Tablet of   %   36   36   20   24   20   20   20   20   32   56   32       Example   1-5   1.8   1.8   1   1.2   1   1   1   1   1.6   2.8   1.6       No. 17                 Comment            Therapeutic agents alone Therapeutic agents show a very bitter taste and aftertaste and results burning and irritating. It is very unpleasant.            Tablet of Example No. 17 A sweet sensation is obtained in the oral cavity, when the milk is added. Tablets have a pleasant taste.             
 
     Example No. 18  
      This example demonstrates the taste-masking effect in a fast melt tablet that includes prednisolone sodium phosphate, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      prednisolone sodium phosphate   1.0 g           skim milk powder   45.76 g            chocolate flavor   2.64 g            polyethylene glycol   3.0 g           sorbitol   20.3 g            xylitol   10.1 g            mannitol   32.8 g            citric acid   1.4 g           aspartame   1.8 g           magnesium stearate   1.2 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 14 except that 10 ml of demineralized water was used instead of 20 ml. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 13 mm in diameter to yield tablets with a thickness of approximately 6 mm and a hardness of about 1 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 600 mg each, contained 5 mg of prednisolone sodium phosphate, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   60   20   40   20   24   20   20   20   36   28   52       agent alone   1-5   3   1   2   1   1.2   1   1   1   1.8   1.4   2.6       Tablet of   %   20   56   20   40   20   20   20   20   20   68   20       Example   1-5   1   2.8   1   2   1   1   1   1   1   3.4   1       No. 18                 Comment            Therapeutic agent alone The therapeutic agent has a bitter and light salty taste.            Tablet of Example No. 18 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 19  
      This example demonstrates the taste-masking effect in a chewable tablet that includes acetaminophen, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      acetaminophen     22 g           skim milk powder   53.02 g            white chocolate flavor     2 g           polyethylene glycol   2.86 g           sorbitol   11.45 g            xylitol   5.72 g           mannitol   18.6 g           citric acid   0.86 g           aspartame   2.29 g           magnesium stearate    1.2 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 19. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 13 mm in diameter to yield tablets with a thickness of approximately 5 mm and a hardness of about 5.5 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 600 mg each, contained 110 mg of acetaminophen, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   40   20   28   36   20   20   20   20   52   24   48       agent alone   1-5   2   1   1.4   1.8   1   1   1   1   2.6   1.2   2.4       Tablet of   %   20   56   20   32   28   20   20   20   28   60   20       Example   1-5   1   2.8   1   1.6   1.4   1   1   1   1.4   3   1       No. 19                 Comment            Therapeutic agent alone It shows a slight bitter taste and aftertaste, similar to vanilla flavor.            Tablet of Example No. 19 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste..             
 
     Example No. 20  
      This example demonstrates the taste-masking effect of the present invention in a fast melt tablet that includes cetirizine di-HCl, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      cetirizine di-HCl   5.0 g           skim milk powder   75.0 g            caramel flavor   5.0 g           polyethylene glycol   5.0 g           sorbitol   30.0 g            xylitol   20.0 g            mannitol   51.5 g            citric acid   2.0 g           aspartame   4.0 g           magnesium stearate   2.5 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 14. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 12 mm in diameter to yield tablets with a thickness of approximately 4.5 mm and a hardness of about 1 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 400 mg each, contained 10 mg of cetirizine di-HCl, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       testers: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   60   20   24   28   36   32   20   28   52   24   60       agent alone   1-5   3   1   1.2   1.4   1.8   1.6   1   1.4   2.6   1.2   3       Tablet of   %   38   50   20   26   26   20   20   20   40   72   30       Example   1-5   1.9   2.5   1   1.3   1.3   1   1   1   2   3.6   1.5       # 20                 Comment            Therapeutic agent alone Therapeutic agent shows a bitter taste and aftertaste, accompanied by a light burning and anesthetic sensations.            Tablet of Example No. 20 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
     Example No. 21  
      This example demonstrates the taste-masking effect in a fast melt tablet that includes fexofenadine, a pharmaceutical agent which is known to have an unpleasant bitter taste.  
                                                      fexofenadine   20.0 g           skim milk powder   100.0 g            caramel flavor    5.0 g           polyethylene glycol   8.33 g           sorbitol   129.67 g            xylitol   50.0 g           mannitol   75.67 g            citric acid    4.0 g           aspartame    4.0 g           magnesium stearate   3.33 g                      
 
      The skim milk powder, sorbitol, xylitol, mannitol, citric acid and aspartame were granulated and dried in the manner described in Example 14, except that 40 ml of demineralized water was used instead of 20 ml. The remaining materials were added to the granules and the mixture was blended for 15 minutes to reach homogeneity. The mixture was tableted by a single punch tableting machine using a toroidal punch of 16 mm in diameter to yield tablets with a thickness of approximately 7.5 mm and a hardness of about 1 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 1.2 g each, contained 60 mg of fexofenadine, and had a pleasant taste when dissolved in the oral cavity.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Therapeutic   %   60   20   20   20   20   52   40   20   48   20   56       agent alone   1-5   3   1   1   1   1   2.6   2   1   2.4   1   2.8       Tablet of   %   60   44   20   20   20   20   20   20   40   44   48       Example   1-5   3   2.2   1   1   1   1   1   1   2   2.2   2.4       No. 21                 Comment            Therapeutic agent alone Fexofenadine shows a bitter taste and aftertaste, accompanied by a burning and irritating sensation.            Tablet of Example No. 21 A sweet sensation is obtained in the oral cavity. Tablets have a pleasant taste.             
 
      For Example Nos. 22 through 25, the ingredients were blended mechanically for 20 minutes at room temperature in a cube mixer. The resulting mixtures were tableted by a single punch tableting machine using a plane punch of 12 mm in diameter to yield tablets with a thickness of approximately 3 mm and a hardness of about 6 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 300 mg each, contained 18.00 mg of vitamin PP, and had a pleasant taste when dissolved in the oral cavity.  
     Example No. 22  
      This example demonstrates the taste-masking effect in a chewable tablet that includes vitamin PP, a therapeutic agent which is known to have an unpleasant taste, and pregelatinized starch.  
                                                      vitamin PP   7.50 g           skim milk powder   100.42 g            aspartame   3.34 g           vanilla flavor   4.17 g           pregelatinized starch   6.25 g           magnesium stearate   3.34 g                      
 
     Example No. 23  
      This example also demonstrates the taste-masking effect in a chewable tablet that includes vitamin PP, and a polyethylene oxide resin.  
                                                      vitamin PP   7.50 g           skim milk powder   104.17 g            aspartame   3.34 g           vanilla flavor   4.17 g           polyethylene oxide resin   2.50 g           magnesium stearate   3.34 g                      
 
     Example No. 24  
      This example also demonstrates the taste-masking effect in a chewable tablet that includes vitamin PP and hydroxypropyl methylcellulose.  
                                                      vitamin PP   15.00 g            skim milk powder   171.67 g            aspartame   6.67 g           vanilla flavor   8.34 g           hydroxypropyl methylcellulose   41.67 g            magnesium stearate   6.67 g                      
 
     Example No. 25  
      This example also demonstrates the taste-masking effect in a chewable tablet that includes vitamin PP and gum arabic.  
                                                      vitamin PP   0.18 g           skim milk powder   1.71 g           gum arabic   1.41 g                      
 
     Example No. 26  
      This example also demonstrates the taste-masking effect in a chewable tablet that includes calcium carbonate.  
                                                      Cal-carb 4450PG (91.6%)   2729.26 g              skim milk powder   1000 g            aspartame   20 g           magnesium stearate   28 g           vanilla flavor   22.74 g                        
 
      Cal-carb 4450PG (91.6%) is a calcium carbonate supplied by CHR Hansen, Inc. of Vineland, N.J., that contains 91.6% in calcium carbonate with the balance comprising maltodextrin and pregelatinized starch. The above ingredients were blended mechanically for 5 minutes at room temperature in a cube mixer to homogeneous granules. The resulting mixture was tableted by a single punch tableting machine to yield tablets with a thickness of approximately 9 mm and a hardness of about 9 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 3.8 g each, contained 1000 mg of calcium carbonate, and had a pleasant taste when chewed.  
                                                                               Number of                                       After   Generally   Generally       tasters: 5   Standardization   Bitter   Sweet   Salty   Warm   Cool   Burning   Irritating   Anesthetic   taste   pleasant   unpleasent                                                                                    Calcium   %   20   20   40   60   20   20   20   20   100   20   92       carbonate   1-5   1   1   2   3   1   1   1   1   5   1   4.6       alone       Tablet of   %   20   80   20   20   20   20   20   20   20   100   20       Example   1-5   1   4   1   1   1   1   1   1   1   5   1       No. 26                 Comment            Calcium carbonate alone Calcium carbonate shows an unpleasant taste and aftertaste.            Tablet of Example No. 26 A sweet sensation is obtained in the oral cavity when the tablets are chewed.             
 
     Example No. C-1  
      This comparative example demonstrates the unacceptable properties of a vitamin PP-containing tablet that includes albumin, a protein found in skim milk powder.  
                                                      albumin   71.11 g            vitamin PP     5 g           aspartame   2.22 g           vanilla flavor   2.78 g           magnesium stearate   2.22 g                      
 
 The above ingredients were blended mechanically to homogeneity for about 15 minutes at about room temperature in a cube mixer. The resulting mixture was tableted by a single punch tableting machine using a plane punch of 12 mm in diameter to yield tablets with a thickness of approximately 12 mm and a hardness of about 0.1 Kp as measured by a Schleuniger tablet hardness tester. The resulting tablets weighed 300 mg each and contained 18 mg of vitamin PP. It was noted that the tablets were unacceptably friable due to the poor binding properties of albumin.