Device for the administration of medicinal substances

A flexible cup contains a medicinal substance and the open face of the cup is pressed against a subject's ear skin by a pin passing through the cup and ear. A compensating member on the end of the pin presses the ear into the cup to maintain contact with the medicinal substance.

BACKGROUND OF THE INVENTION 
The present invention relates to a device for the administration of 
medicinal substances. More particularly, a device to be applied to the 
skin of the ear of a subject, especially of an animal. 
Numerous means for the administration of medicinal substances, especially 
to animals, are known. These devices may be applied to the skin of 
different parts of the body, such as the ears, the neck, the shoulder, the 
tail or the nasal cavities, or again the mucosa of the genital organs of a 
subject. These known means are in different forms, such as adhesive tape, 
receptacles of different types, perforating plates. These known means are 
maintained in place, for example, by adhesives or with the aid of 
different mechanical devices, such as clips, fasteners, pins, spikes or 
clamps. It was found that the use of the devices of the prior art was not 
always satisfactory with respect to the maintenance in place, the 
tightness and the optimum penetration of the medicinal substance to be 
administered. Thus, for example, the fixation of such means with the aid 
of an adhesive often requires the initial shaving of the hair and cleaning 
of the skin and in addition to bond frequently did not resist all of the 
exigencies of the life of the subject. Means maintained in place with the 
aid of mechanical devices, even if they are kep in place better, do not 
always achieve a satisfactorily tight bond between said means and the 
skin. The mechanical means do not insure the permanent contact between the 
surface of skin intended to enter into contact with the medicinal 
substance, which is indispensable for optimum absorption. This 
inconvenience is often encountered when the medicinal substances to be 
applied are in the form of ointments, cream or gels. Some of the known 
means have attempted to solve this problem of the application of 
substances having the consistency of cream, ointments or gels by using 
aluminum cups as the receptacles, the cups being attached to the ear of 
the subject by means of a pin. Even though the cup is deformed during its 
placement, after the operation of placement, it retains the form and 
volume received. Because of this fact, the layer of the medicinal 
substance initially in contact with the skin is absorbed and a space is 
created between the absorbent surface of the skin and the substance in 
question, which is contained in the cup. There is, therefore, a risk that 
the medicinal substances remains partially unabsorbed. Another known means 
consists of a cup of a plastic material, of a more or less elastic nature, 
which is secured to the ear of the subject with several pins. The 
medicinal substance is introduced in the form of a solution previously 
adsorbed on a solid support, such as a porous disk of burned clay. After 
the placing of this means of administration, the solid support rests in 
the cup and is maintained in permanent contact with the skin by a spring 
resting against the bottom of said cup. As a result, even if the cup is 
made of an elastic material, the potential elasticity of the cup never has 
the effect of moving the bottom of the cup closer to the skin. This 
potential elasticity, therefore, serves only to assure the contact of the 
edge of the cup with the skin. This means of administration is suitable 
only in the case of a solid support which previously had adsorbed a 
medicinal solution. Consequently, it is obvious that in the case where a 
medicinal substance having the consistency of an ointment, a cream or a 
gel must be administered such a means of administration cannot be used. 
(French Pat. No. 2 292 489 and U.S. Pat. No. 3,788,296 describe a device 
for the application of a medicinal substance to the skin of an animal. 
Devices used to mark the animals which comprend a pin through the skin are 
described in U.S. Pat. No. 1,390,342 and French Pat. Nos. 335 245, 740 
203, and 858 267) 
SUMMARY OF THE INVENTION 
The device of the present invention was developed to remedy the 
difficulties described above. Nevertheless, in the course of its 
development it was found that when a medicinal substance in the form of a 
pharmaceutical preparation having the consistency of an ointment, a cream 
or a gel, is administered contained in a receptacle applied to the skin of 
the ear of a subject, a free space is formed between the absorbent surface 
of the skin and said medicinal substance, after the layer of said 
substance placed in contact with the skin has been absorbed. This fact 
interferes with the regular and complete process of absorption of the 
medicinal substance on the one hand and on the other, may cause harmful 
changes on the absorbent surface of the skin, such as the formation of a 
scab. 
Therefore, in order to be able to successfully administer through the skin 
of the ear of a subject a medicinal substance in the form of a 
pharmaceutical preparation having the consistence of an ointment, a cream 
or a gel, it is necessary to employ a device capable of assuring the 
permanent contact of such a substance with the surface of the skin of a 
subject. The device which is the object of the present invention, is based 
on the fact that a permanent contact between said medicinal substance to 
be administered and the surface of the skin of a subject may be assured 
successfully only in the case where the structural elements of the device 
are exposed to pressure, having the effect of urging said substance 
against the surface of the skin. 
The device for the administration of medicinal substances which is the 
object of the present invention and is useful in medicine, comprises a 
means of fastening to the skin of the ear of the subject, such as a pin or 
a spike serving both to maintain the assembly of the device and its 
maintenance in place and is characterized by the fact that it comprises 
further: 
a hollow cup to receive the medicinal substance, said hollow cup being 
deformable elastically when subjected to pressure, and 
compensating means capable of exercising, directly or otherwise, pressure 
on the hollow cup and simultaneously on the skin of the subject to cause 
the means to penetrate into the hollow cup and to maintain said pressure. 
The device may be further characterized by the following items: 
the hollow cup is an integral part of the fastening means; 
the hollow cup consists of a piece which is independent of the fastening 
means, the piece being joined to said means before or after the placing of 
the device; 
the compensating means consists of an elastic element, capable of receiving 
the fastening means; 
the compensating means comprises two distinct elements, the first being an 
elastic element proper and the second a support capable of receiving the 
fastening means; 
the return piece (or compensating means) is constituted by a resilient dome 
cut out in the form of a rosette of which the "petals" are fairly 
numerous, 
the wall of the hollow dome (or hollow cup) containing the medicinal 
substance is provided with one or more concentric grooves, 
the wall of the hollow dome containing the medicinal substance is partially 
cut out at its periphery, 
the hollow dome containing the medicinal substance comprises one or more 
reduced areas situated between its top and its rim, and 
the fixing means is provided, in its portion intended to be placed in the 
return piece, with a thread and its opposite enlarged end is in the form 
of a polyhedron. 
The device of the present invention functions as described hereafter. 
Because of the choice of the elements of the device of the invention and 
their arrangement, the hollow cup after its placement, has its edge in 
contact with the skin of the subject, while the compensating means exerts 
pressure on the wall of said hollow cup. The latter in turn exerts 
pressure on the medicinal substance contained in it. Simultaneously, the 
skin of the subject is pushed toward the inside of the hollow cup. At the 
rate at which the layer of the medicinal substance placed in contact with 
the surface of the skin, is absorbed by the latter, a new quantity of the 
medicinal substance is, under the pressure of the cup, moved toward the 
skin, thus replacing the layer absorbed. In this manner, permanent contact 
between the medicinal substance and the skin is assured. 
It may be said that the bollow cup of the device of the present invention 
acts in the manner of the membrane of a pump, for example, which 
constantly moves the medicinal substance toward the abosrbent surface of 
the skin by pressure. Because of this, absorption takes place under 
optimum conditions and may be continued, if desired, until the medicinal 
substance contained in the hollow cup is exhausted. 
Research has demonstrated also that if the skin, through which the 
absorption is to take place, is simultaneously urged toward the inside of 
the hollow cup, the contact between the skin and the cup is further 
improved, which insures improved tightness of fit of the device. It should 
also be mentioned that upon the penetration of the skin into the hollow 
cup, it stretches and becomes more capable of absorption. The device of 
the invention provides, as mentioned above, an excellent yield of 
absorption of a medicinal substance and by the same token is of 
considerable economic interest, the more so, since with previous devices 
the medicinal substance is frequently not absorbed in its entirety, 
resulting in a significant loss. It is equally important to take into 
consideration the fact that it is difficult to observe and to study the 
action of a medicinal substance if all of the amount administered has not 
been absorbed. This may happen frequently with the prior means of 
administration. 
The device of the invention has also the advantage of easy removal from the 
subject. The ease with which this may be accomplished permits ready 
control of the duration of the absorption of the medicinal substance and 
the verification of the amounts absorbed. The absorption of a given 
substance may thus be interrupted at any moment, according to need. 
The device further eliminates the inconvenience inherent particularly in 
devices already known and applied to the nasal cavities, the inconvenience 
being represented by the danger of such a device coming into contact with 
food and more particularly with liquids ingested by the subject. This 
results in a loss of said medicinal substance that is difficult to 
control. In the embodiment of the invention, the hollow cup may be an 
integral part of the fastening means or again it may consist of a piece 
independent of the fastening means. The term "to be an integral part" used 
in the foregoing refers to the part of the device of the invention that is 
obtained after machining or, in the alternate case, an assembly ready for 
use. The term includes an embodiment in which the hollow cup and the 
fastening means are produced by machining in a single piece, either of the 
same or different materials. This single piece may be made, for example, 
by casting. In this case, the material and the thickness of the wall of 
the cup is selected so that it is able to perform the function assigned to 
it, i.e. to deform elastically. Concerning the fastening means, if it is 
made of the same material as the hollow cup, its diameter is chosen to 
assure the rigidity necessary for the placement of the device of the 
invention. In the case where the fastening means is made of a material 
different from that of the hollow cup, the choice of its dimensions 
depends only on the arrangement of the device. 
In a second embodiment of the device of the invention, the term "to be an 
integral part" may denote a hollow cup made separately from the fastening 
means, and which is then securely attached to said fastening means, 
following the fabrication of the latter. 
In a third embodiment the hollow cup is not an integral part of the 
fastening means; it is made as an independent piece and is not combined 
with the fastening means until immediately prior to the use of the device. 
The hollow cups of the different embodiments, once made, are filled with a 
pharmaceutical composition. They are then conditioned to be ready for 
distribution and application. After conditioning, the pharmaceutical 
composition contained in the hollow cup is covered, for example, by a 
protective film, which is removed prior to use. 
The hollow cup is made of a material capable of elastic deformation under 
the effect of the pressure of the compensating means, thus allowing the 
wall of the cup to approach the skin and to reduce, in the majority of 
cases, the volume of the cup. This material may consist of a plastic 
having the necessary properties of elastic deformability, such as a 
natural or synthetic elastomer, polyvinyl chloride, polyethylene, 
polypropylene or nylon. 
In a fourth embodiment, the compensating means, as mentioned above, may 
consist in one embodiment of an elastic element, designed in a manner so 
as to be capable of simultaneously receiving the fastening means. 
In a fifth embodiment, the compensating means comprises two distinct 
elements, one of which is the elastic element proper and the other a 
support designed to receive the fastening means. The two pieces are 
assembled immediately preceding their use following the placement of the 
device of the invention. They may also be assembled at any time between 
their making and their use. 
In a sixth embodiment of the present invention the return piece being 
constituted by a resilient dome is cut out in the form of a rosette. By 
way of example it is associated, by a fixing means, with a hollow dome as 
described above. 
Such a return piece, while fulfilling its role of exerting pressure on the 
hollow dome, permits the blood circulation in the ear of the subject to 
take place under excellent conditions. The risks of circulatory disorders, 
even very slight ones in the blood vessels in this region of the skin are 
therefore eliminated. 
The number of "petals" of the rosette can vary according to the material 
used and according to the desired pressure. By way of example this number 
can be from three to sixteen. 
So as to facilitate maintenance of the point of the fixing means the return 
piece can be provided, in its central portion intended to allow passage of 
the said point, with several abutments. 
When the point has passed through the return piece the abutments force it 
to remain in the established position and thus ensure that the device is 
maintained in place. These abutments can also be advantageously replaced 
by a thread. 
In a seventh embodiment of the present invention the return piece described 
above can be associated with a hollow dome provided with one or more 
concentric grooves. 
Hence, such a hollow dome which has a wall which is thinner at the place 
where a concentric groove is disposed, becomes more supple and responds 
better to the stresses due to the pressure exerted by the return piece. 
By way of example the wall of this hollow dome can be provided with two 
concentric grooves. 
In an eighth embodiment of the present invention the return piece described 
above is associated with a hollow dome of which the wall is partly cut out 
at its periphery. 
The depth of these cut-outs is selected depending upon the qualities of the 
material from which the hollow dome is made and upon the resilience which 
it is desired to give to it, so that it can exert a desired pressure upon 
the medicinal substance. 
By way of example the depth of these cut-outs in the wall can vary between 
one-fifth and two-thirds of the radius of the dome. The number of cut-outs 
can vary between, for example, two and thirty two. 
This way of making the hollow dome, while ensuring regulation of the 
pressure exerted by the latter on the medicinal substance contained 
therein, also enables the contact between the said substance and the skin 
of the subject to be improved. 
This type of dome is especially very useful in the case in which the 
medicinal substance is in the form of an ointment of thick consistency. 
In a ninth embodiment of the present invention the return piece described 
above is associated, by a fixing means, with a hollow dome of which the 
wall comprises one or more reduced areas situated between its top and its 
rim. 
This reduced area of the hollow dome thus makes it more supple and capable 
of responding more easily to the pressure exerted by the return piece and 
at the same time of improving the transfer of this pressure to the 
medicinal substance contained therein. 
In a tenth embodiment of the present invention a hollow dome and a return 
piece, as described above, can be associated by a fixing means of which 
the portion intended to be placed in the return piece is provided with a 
thread. 
This manner of making up the fixing means such as, for example, a spike, 
enables once the device has been placed, the pressure of the return piece 
on the said hollow dome to be readjusted, increased or reduced and permits 
the two members in question to be brought closer together or separated, by 
shortening or increasing the distance between the tops of the said members 
by screwing or unscrewing the said fixing means. 
During screwing or unscrewing of the said fixing means the screw thread 
with which it is provided, given the nature of the material from which the 
return piece is made, can easily be engaged with and screwed into the 
abutments of the said return piece. 
The central portion of the return piece in which is placed the fixing means 
can also, as already stated, be provided with a thread in place of 
abutments, corresponding to the thread with which the fixing means is 
provided. The readjustment of the pressure exerted by the return piece on 
the hollow dome will also be easy. 
To facilitate screwing or unscrewing of the said fixing means its enlarged 
end opposite the threaded portion which can be called the head is made in 
the form of a polyhedron, such as the tri, tetra, penta or hexahedron. 
This method of working can be useful espeically when, after the subject has 
carried the device of the invention for a fairly long time, it is desired, 
at a given moment, to readjust the pressure which the hollow dome exerts 
upon the medicinal substance in the form of an ointment which it contains. 
In the case in which the fixing means is, for example, a spike, the head of 
which is round, the diameter of this head can vary. 
By way of example in the embodiments in the device of the present invention 
the diameter of this head can be greater than the diameter of the body of 
the spike by an amount of from one fifth greater up to twice as great or 
even more. 
The compensating means is made of a material having the elastic properties 
required to exercise the pressure on the hollow cup necessary to make the 
wall of said cup approach the skin. Because of this, the hollow cup is 
able to exercise a constant pressure upon the substance to be 
administered. This pressure force is also necessary to urge the skin into 
the cup. Such a material may consist, for example, of an elastic plastic 
substance, or a material of a metallic character, such as steel, a bronze 
or various other alloys. The pressure exerted by the compensating means 
being on the skin of the subject on the one hand and on the hollow cup on 
the other, consequently the pressure exerted by the hollow cup on the 
medicinal substance contained in the cup, must be in equilibrium. This 
equilibrium depends on the choice of materials used for the hollow cup and 
the compensating means and also on the consistency of the pharmaceutical 
composition including the medicinal substance to be administered. The 
force of the pressure to which the hollow cup is exposed following the 
placement of the device, is chosen by taking into account that at the rate 
at which medicinal substance is absorbed, the hollow cup urges new 
quantities of said substance toward the skin, under the effect of the 
compensating means. As a result, because the hollow cup is approaching the 
skin, the compensating means is extended and at the same time the pressure 
exerted by it, diminishes. It is important that the force of the pressure 
exerted by the compensating means be dimensioned with care so that it will 
be capable of performing its function from the placement of the device to 
the rate of absorption of the medicinal substance. The choice of the 
pressure that must be provided by the compensating means, the thickness of 
the skin of the ear of the subject, the elastic deformability of the 
hollow cup and its dimensions, the consistency of the pharmaceutical 
composition, together with the length of the fastening means chosen, play 
important roles in the design and the use of the device of the invention. 
It is also important, that the pressure exerted by the compensating means 
on the skin of the subject and on the hollow cup, and consequently, by the 
edge of said cup on the skin of the ear, be chosen, in addition to the 
criteria already mentioned, by taking into account the blood circulation 
in the part of the skin of the ear outlined by the device of the 
invention, after its placement. Excessive pressure by the compensating 
means could cause serious circulatory problems in the blood vessels of 
this region of the skin and provoke, in an extreme case, the onset of 
necroses. 
As an example of an embodiment of the device of the invention, the hollow 
cup may have a thickness of 1 to 2 mm, an internal diameter of at the base 
of approximately 30 mm, an edge thickness of approximately 5 mm, a height 
of approximately 10 to 15 mm, which together yield a capacity of 
approximately 3 cm.sup.3. 
Concerning the compensating means, the internal diameter of the base of the 
cup must be taken into account, so that the skin of the ear may fold 
slightly under the effect of the pressure and penetrate into the hollow 
cup, without otherwise risking a "fracture" of the ear in relation to the 
edge of the cup. The bend of the skin of the ear after its penetration 
into the cup should be gentle in order to prevent the circulatory troubles 
already mentioned and to provide a good application of the edge of the cup 
against the skin, together with a satisfactory tightness of the device. If 
the condition of maximum tightness is not satisfied, leaks of the 
medicinal substance may develop at that location, given the pressure under 
which said substance is maintained in the cup. In order to satisfy these 
requirements, the diameter of the part of the compensating means which 
makes contact with the skin of the subject should, in general, be less 
than the internal diameter of the base of the hollow cup. Its order of 
magnitude may vary, for example, from 2/10 to 9/10 of said internal 
diameter of the base of the hollow cup. One may, therefore, as an example, 
determine that satisfactory results may be obtained with a compensating 
means having a part which enters into contact with the skin of the ear, 
with a thickness of 10 mm, and a diameter comprised between 5/6 and 1/3 of 
the internal diameter of the hollow cup. Such a device is constituted by a 
hollow cup with an internal base diameter of 30 mm, and a compensating 
means having a diameter of the part entering into contact with the skin of 
between 25 and 10 mm, the thickness of the ear being approximately 10 mm. 
The height of the compensating means is chosen as a function of the design 
of the piece, the nature of the material of which it is made and the force 
of the pressure it is to exert on the hollow cup and on the skin. In the 
case of the device described above, it is of the order of 10 to 25 mm. The 
length of the fastening means, in the form of a pin, for the example 
presented in the foregoing, is of the approximate order of magnitude of 30 
to 40 mm. In any case, it should be chosen as a function of the height of 
the compensating means, the thickness of the skin of the ear, the height 
of the hollow cup and also of the pressure exerted by the compensating 
means on the hollow cup. The placement of the device of the invention may 
be effected with the aid of a clip, such as those used to mark the 
animals. In the case where the hollow cup is an integral part of the 
fastening means, the placing of the device of the invention may be 
performed without any preliminary operation. In contrast, in a case where 
the hollow cup is provided, after manufacturing, in the form of a single 
piece, independent of the fastening means, it is necessary to place the 
device of the invention first and then combining said means with the 
latter, by placing it upon the device. Once the device of the invention is 
put in place, it may be easily removed at any time. It is sufficient for 
the purpose to cut, with the aid of pliers, the end of the fastening means 
placed at the side opposite to the hollow cup. Due to the arrangement of 
the device of the invention and its elasticity, the end of the fastening 
means may be disengaged by a simple pressure upon said device and the 
cutting operation performed with ease.

In the drawings: 
1 represents the fixing means; 
2 the hollow dome being made during working in single piece with the fixing 
means; 
3 the hollow dome constituted by an independent piece; 
4 the return piece constituted by a resilient return piece in the form of a 
resilient dome serving simultaneously as support in which is placed the 
fixing means 1; 
5 the return piece constituted by a resilient return member in the form of 
a hollow dome requiring a separate support in which is placed the fixing 
means 1; 
6 the return piece constituted by a resilient return member in the form of 
a spring requiring a separate support in which is placed the fixing means 
1; 
7 the return piece constituted by a resilient return member in the form of 
a spring adapted at one of its ends so as to be capable of serving 
simultaneously as a support in which is placed the fixing means 1; 
8 the support in which is placed the fixing means constituted by an 
independent piece; 
9 the return piece constituted by a resilient return member in the form of 
a dome of which the base is closed, serving simultaneously as support in 
which is placed the fixing means 1; 
10 the skin of the ear of the subject; 
11 the medicinal substance to be administered in the form of a 
pharmaceutical preparation having the consistency of an ointment, a cream 
or a jelly; 
12 the hollow dome worked as an independent piece which is then associated 
finally after working with the fixing means to form a single piece; 
13 the return piece constituted by a resilient return member in the form of 
a resilient bulb arranged so as to be capable of serving simultaneously as 
support in which is placed the fixing means; 
14 the return piece constituted by a resilient dome cut out in the form of 
a rosette; 
15 the head of the fixing means of which the diameter is reduced by 
comparison with the diameter of the head of the fixing means appearing in 
FIGS. 1 to 8; 
16 the abutments with which the central portion of the return piece 14 is 
provided; 
17 the hollow dome provided with the concentric grooves 18; 
19 the head of the fixing means in the form of a hexahedron; 
20 the thread with which the fixing means is provided in its portion 
intended to be placed in the central portion of the return piece 14; 
21 the hollow dome comprising a reduced area 22 (of a slight thickness); 
23 the hollow dome partially cut out at its periphery. 
As already indicated FIGS. 1 to 16 illustrate a certain number of 
embodiments of the device which forms the subject of the invention. 
Nevertheless, starting with the members described above it is possible to 
carry out numerous permutations both regarding the forms of these members 
and regarding the methods of making them up, their arrangement and their 
placing with respect to the skin of the ear of the subject, or to combine 
them in a very varied manner.