Abstract:
An oral syringe of the type having a syringe barrel terminating in a syringe neck with a blunt orificed end is combined with a medication bottle provided with a self resealing elastomeric closure designed for admitting the syringe neck into the bottle while maintaining a sufficient liquid tight seal against the syringe neck to allow a dose of medication to be drawn from the bottle in an inverted condition of the bottle without significant leakage. The elastomeric closure may be initially unbroken and rupturable under urging of the orificed end for passing the syringe neck into the bottle, the closure resealing itself upon withdrawal of the syringe neck.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention generally pertains to methods and devices useful for the administration and delivery of liquid oral medications and more particularly concerns a self resealing closure for medication bottles containing liquid medication drawn and administered by oral syringes. 
         [0003]    2. State of the Prior Art 
         [0004]    The administration of liquid medications such as cough and cold medicines, whether over the counter or prescription medication, to young children and infants requires careful control over dosage. In the case of adults the dosage of such medications is often measured by tea or table—spoonfuls. The spoons may vary in size to a considerable degree, and they may be filled to different levels, resulting in substantial variations in the administered dose. Adults, because of their larger body mass, are unlikely to suffer adverse effects from such variations. However, small children, having much smaller body mass, have often suffered adverse consequences and in fact result in thousands of children being hospitalized each year. Similar problems occur when unsupervised children gain access to and take such medicines, which are often colored and flavored to appeal to children&#39;s tastes, and thus may receive an overdose of the medicine. The aforementioned difficulties are compounded when the liquid medications are concentrated and intended for administration with a dropper. A parent may think little of giving a child an extra drop or two, thinking it is a harmless amount, but in fact this too may have undesirable and harmful outcomes in the case of small children. 
         [0005]    More recently this problem has been addressed through the use of oral syringes which more accurately measure and dispense small volumes of liquid medication in a consistent manner. Oral syringes differ from conventional hypodermic type syringes in that the neck extending from the end of the syringe barrel is sized such that standard hypodermic needles cannot be mated to it. Instead, the oral syringe is used to deliver a stream of liquid medication to the oral cavity of young patients, who are often uncooperative. 
         [0006]    The liquid medication is drawn by immersing the open end of the neck of the syringe in the contents of the medication bottle and pulling the syringe plunger from the barrel in the conventional manner. The neck of the medication bottle typically does not admit the syringe barrel into the bottle, so that the liquid contents must be brought within reach of the syringe end by tilting the bottle. However, as the contents of the bottle are consumed and depleted, the liquid level drops and it becomes necessary to incline the bottle to an increasing degree so as to bring the liquid within reach of the short neck of the oral syringe. This can be difficult to accomplish without spilling some of the contents. This process has been somewhat facilitated through the use of a plug fitted into the neck of the medication bottle and having a plug opening of reduced diameter relative to the diameter of the bottle neck. The plug opening admits the syringe neck into the bottle neck but also provides an interior rim which helps contain the liquid contents while the dose is drawn into the syringe. Also, the barrel end may be pressed against the plug to further help contain the liquid during this operation. 
         [0007]    Nonetheless, the use of oral syringes with liquid medications remains inconvenient and dependent to an undesirable degree upon the manual dexterity of the user. 
       SUMMARY OF THE INVENTION 
       [0008]    According to the present invention, a liquid oral medication bottle is provided with a self resealing elastomeric closure normally sealing the bottle and adapted to admit the syringe neck into the bottle while maintaining a substantially liquid tight seal between the elastomeric closure and the syringe neck. The neck of the oral syringe has an orificed blunt end which is inserted through the elastomeric closure into the bottle. The bottle is tilted or inverted such that the orificed blunt end is immersed in the liquid medication contained in the bottle, and a dose of the medication is drawn into the syringe barrel. The syringe neck is withdrawn from the bottle to allow self resealing of the elastomeric closure. 
         [0009]    In one embodiment of the invention the elastomeric closure is initially unbroken and the method further comprises the step of urging the orificed blunt end of the syringe neck against the elastomeric closure with sufficient force for rupturing the closure and passing the neck&#39;s orificed end therethrough and into the bottle. 
         [0010]    The elastomeric closure preferably has a septum of elastomeric material, the septum having a generally depressed dished portion including an area of minimum thickness. The dished portion increases in thickness radially from the minimum thickness to a much thicker elastomeric material encompassing the area of minimum thickness, the depressed portion and the area of minimum thickness being shaped and configured to elastically distend for passing the blunt orificed end of the syringe neck through a tear in the area of minimum thickness. The septum self recloses by returning opposite edges of the tear to a substantially contiguous closed condition after withdrawal of the syringe neck from the septum. 
         [0011]    These and other improvements, features and advantages of the present invention will be more clearly understood by reference to the following detailed description of the preferred embodiment taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  shows a prior art plug of the type fitted in liquid medication bottles for use in conjunction with an oral syringe; 
           [0013]      FIG. 2  is a cross sectional view of the plug of  FIG. 1  taken along line  2 - 2  in  FIG. 1 ; 
           [0014]      FIG. 3  is a top side perspective view of the improved plug with the self resealing elastomeric closure according to the present invention; 
           [0015]      FIG. 4  is a cross sectional view taken along line  4 - 4  in  FIG. 3 ; 
           [0016]      FIG. 4   a  is an enlarged cross section as in  FIG. 4 ; 
           [0017]      FIG. 5  is a top side perspective view of a typical medication bottle fitted with the plug of  FIGS. 3 and 4 ; 
           [0018]      FIG. 6  is a cross section taken along line  6 - 6  in  FIG. 5 ; 
           [0019]      FIG. 7  illustrates how the neck of the oral syringe is inserted through the elastomeric closure of the inverted medication bottle of  FIGS. 5 and 6 ; 
           [0020]      FIG. 8  shows how a dose of liquid medication is drawn into the oral syringe from the inverted medication bottle; 
           [0021]      FIG. 9  is a cross section taken along line  9 - 9  showing the sealing engagement of the elastomeric seal about the exterior surface of the syringe neck; 
           [0022]      FIG. 10  is a view taken as in  FIG. 9  showing the self resealing of the elastomeric closure to a substantially liquid tight condition upon withdrawal of the oral syringe; and 
           [0023]      FIG. 11  illustrates typical delivery of the medication dose by the oral syringe to the oral cavity of a child. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    With reference to the accompanying drawings in which like numerals reference like elements,  FIGS. 1 and 2  show a prior art plug of the type fitted in the neck of liquid oral medication bottles in order to facilitate the drawing of the liquid medication into an oral syringe. 
         [0025]    The prior art plug generally indicated by numeral  10  has a plug top  12  in which is defined a circular depression  14  bounded at a lower end by an interior annular flange  16  which encompasses a center hole  18  through the plug top. Plug  10  also has a cylindrical side wall  22  open at a lower end  22   a  and from which extend four axially spaced radial ribs  24 . The center hole  18  provides a reduced aperture when plug  10  is pressed into the neck of a medication bottle and interior flange  16  provides an annular containment dam which helps reduce the likelihood of spillage when the medication bottle is tilted or inverted onto the oral syringe. Nonetheless, substantial dexterity of the user on the part of the user is needed to avoid spillage of the liquid medication. 
         [0026]      FIGS. 3 and 4  show an improved plug  30  according to the present invention. In plug  30  a self resealing elastomeric closure  32  closes the center hole  18  of the prior art plug  10 . The prior art plug structure (hereafter referred to as shell  10 ) is used in the plug  30  of this invention as a supporting shell for the self resealing closure  32 . The self resealing elastomeric closure  32  includes a one piece closure body  34  supported in an interference fit above and below the inner flange  16  of shell  10 , such that the closure body  34  is permanently locked to the shell  10 . 
         [0027]    In a presently preferred method of manufacture plug  30  is manufactured in a two step process, in which the shell  10  is molded first and closure  32  is then molded onto the shell  10 . This two step process permits different materials to be used for the two components, each suited to its function. The closure body is preferably molded of a relatively soft thermoplastic elastomeric material, for example, GLS2711 sold by GLS Thermoplastic Elastomers based in McHenry, Ill., a business unit of PolyOne Corporation of Avon Lake, Ohio. The plug shell  10  is preferably made of a harder, stiffer thermoplastic material such as polypropylene, a presently preferred material being a 50-50% blend of polypropylene and Synprene thermoplastic elastomer available from PolyOne Corporation. 
         [0028]    The closure body  34  is generally disk shaped with a central depression  36  including a dished septum  40  in the top surface  38  of the closure body  34 . As best seen in  FIG. 4   a , the septum  40  has a generally depressed dished portion  42  including an area of minimum thickness  44  as measured between the septum bottom and the underside or interior surface  46  of the closure body  34 . The dished portion  42  of septum  40  increases in thickness radially from the minimum thickness  44  to a much thicker elastomeric material  48  encompassing the area of minimum thickness. 
         [0029]    It has been found advantageous to provide a greater minimum thickness of elastomer in the self resealing closure  32  intended for perforation by the neck of an oral syringe than the smaller minimum thickness preferred in previous filings and earlier disclosed embodiments of the perforable self-resealing elastomeric closure of this invention. For example, in a plug  30  of nominal 20 mm diameter the overall thickness of closure body  34  may be approximately 3 mm, the diameter of central depression  36  at the top surface  38  may be 4.80 mm, the depth of the central depression  36  may be 1.5 mm deep and the minimum thickness at the center of the closure body  34  may be 1.6 mm thick. For a 24 mm diameter plug  30  the thickness of closure body  34  may be approximately 4.25 mm, the diameter of central depression  36  at the top surface  38  may be 5.5 mm, the depth of the central depression  36  may be 2.00 mm deep and the minimum thickness at the center of the closure body  34  may be 2.25 mm thick. In general, the minimum thickness  44  at the bottom of the dished portion  42  in plug  30  may be approximately equal to the depth of the central depression  36 . 
         [0030]      FIGS. 5 and 6  illustrate a typical medication bottle B fitted with the self resealing elastomeric plug  30  of  FIGS. 3 and 4 . As shown in  FIG. 6 , when the plug  30  is press-fitted into the bottle neck N, the radial ribs  18  are flexed upwardly from their normal radial condition and the inherent resilience of the elastomeric rib material presses the ribs  18  against interior of the cylindrical bottle neck in a friction fit which both retains the plug  30  in the bottle neck N and also provides a liquid tight seal for containing the liquid contents L from leaking between the plug and the bottle neck. The bottle neck N also has an exterior thread T onto which is screwed a removable twist-on bottle cap C. In an initial condition of elastomeric closure  32  the septum  40  is unbroken, i.e., forms a continuous closed partition across the bottle neck N, as seen in the cross section of  FIG. 6 . 
         [0031]      FIGS. 7 and 8  illustrate how a dose of liquid medication is drawn with a typical oral syringe S from medication bottle B provided with the plug  30  of this invention. Oral syringe S may be a commercially available syringe having a syringe barrel  100  with a syringe neck  102  at a proximal end of the barrel  100  and a syringe plunger  106  slidable within barrel  100 . Syringe neck  102  extends from an end wall  104  of the syringe barrel. The syringe neck  102  is a cylindrical or tapering stub terminating in a generally blunt end  108 . A bore  110  through syringe neck  102  opens in an orifice  112  in the blunt end  108  and communicates with the interior of the syringe barrel  100 , as best seen in  FIGS. 9 and 10 . 
         [0032]    The depressed dished portion  42  and the area of minimum thickness  44  are shaped and configured to rupture and elastically distend for under the urging of the blunt orificed end  108  of the syringe neck  102  and passing the orificed end  108  and a portion of neck  102  through a tear  120  created in the area of minimum thickness  44  of the septum  40 , a condition depicted in  FIG. 9 . The dished portion  42  and the area of minimum thickness  44  are self reclosing by returning opposite edges  120 ′ of the tear to a substantially contiguous closed condition after withdrawal of the syringe neck  102  from the torn septum, as shown in  FIG. 10 . 
         [0033]    Preferably, the shape and diameter of the upper portion  50  of the central depression  36  is sized to closely receive the syringe neck  102 , The upper portion  50  helps guide the neck of the syringe and to hold it in general alignment with the center of the area of minimum thickness  44  of dished septum  40  as the syringe neck  102  is advanced into the depression  36  and urged against the depressed portion  42  to rupture or tear the area of minimum thickness and through septum  40 , thereby to place the orifice  112  on the blunt end  108  at the end of the syringe neck into fluidic communication with the interior of the medicine bottle N, a condition seen in  FIGS. 8 and 9 . 
         [0034]    As shown in  FIG. 8 , the medication bottle with the fluidically coupled oral syringe may be held inverted or upside down so that the liquid contents L in the bottle N overlie the orifice  112  of the syringe neck. In this position, the plunger  106  of the oral syringe S may be pulled from the syringe barrel  100 , thereby to draw a dose D of liquid medication L into the syringe barrel. The prescribed dosage is measured by aligning the plunger bottom with a corresponding marker  114  on the syringe barrel. 
         [0035]    In the fluidically coupled condition of  FIG. 8 , the perforated elastomeric closure  32  is distended to admit passage of the syringe neck  102  and because of its inherent elasticity forms a tight seal about the exterior surface of the syringe neck, as in  FIG. 9 . A close fit between syringe neck  102  and upper portion  50  of depression  36  further assists in preventing leakage. Consequently, the liquid L is contained in the bottle B and does not leak onto the underlying syringe S. 
         [0036]    Once the desired dosage D has been drawn, the oral syringe S is withdrawn from the bottle B, whereupon the elastomeric closure  32  is free to self reseal to a substantially liquid tight condition, as indicated in  FIG. 10 . 
         [0037]    The improved plug  30  with the self resealing closure  32  of this invention provides a number of advantages over the prior art plug of  FIGS. 1 and 2 . 
         [0038]    Firstly, the normally closed condition of the elastomeric septum, both before and after perforation with a syringe S, prevents contamination of the contents L with dust or any pollutants present in the immediate environment even while the bottle cap C is removed. 
         [0039]    Secondly, the normally closed condition of the elastomeric closure makes the medication bottle doubly childproof, i.e., even if the twist-on cap C is forgotten, or even if it is removed by the child, the child is unable to drink from the bottle contents, which remain secure even if the bottle is turned upside down or tilted into the child&#39;s mouth. 
         [0040]    Thirdly, the bottle is leak proof with or without the twist-on cap C as a result of the normally closed, substantially liquid tight elastomeric closure  32 . 
         [0041]    Fourth, the bottle can be upended onto the oral syringe S with little risk of leakage or spillage of the liquid medication L. This is an improvement over the prior art where continuous care had to be observed while drawing the liquid medication into the oral syringe to prevent spillage through the open hole of the prior art plug. 
         [0042]    The plug  30  can be made in various diameters and dimensions to fit medication bottles or other containers having container or bottle necks N of different dimensions. The upper diameter of the central cavity  36  in each case is guided by the neck diameter of the oral syringe S to be used with that combination of plug  30  and container B. For example, oral syringes in 5 ml, 10 ml and 20 ml capacities are in general use and have syringe necks  102  of varying sizes, typically 3 to 4 mm in diameter. In each case, the diameter of upper portion  50  of the center cavity of the plug is sized accordingly to closely receive the diameter of the syringe neck. 
         [0043]    It should be understood that in alternate embodiments of the invention the central cavity  36  may be inverted on the closure body  34  so that the cavity opens into the interior of the medicine bottle B and the dished septum faces the bottle interior. 
         [0044]    While particular embodiments of the invention have been described and illustrated for purposes of clarity and explanation it should be understood that still other changes, modifications and substitutions will be apparent to those having only ordinary skill in the art without departing from the scope of the present invention as defined in the following claims.