JPS61268619A - Animal drug pharmaceutical coated with polymer - Google Patents

Abstract

PURPOSE:An animal drug, obtained by coating the surface of a granular pharmaceutical of an animal drug coated with a hydrophobic waxy material further with a water-soluble polymer, and used for oral administration by mixing in a feed, etc. CONSTITUTION:An animal drug pharmaceutical, obtained by coating an animal drub, e.g. antibiotic, sulfamide agent or nitrofuran based drug, with <=1pts.wt., particularly 5-50pts.wt., based on 100pts.wt. animal drug, hydrophobic waxy material, e.g. higher fatty acid, hardened natural fat or oil or natural wax, and coating the resultant granular pharmaceutical further with a water-soluble polymer, e.g. methyl cellulose, cellulose acetate or gelatin adjusted to preferably 2-5,000cps viscosity, capable of preventing the bitterness of the drug, and readily and orally administrable. If it is difficult to obtain the granular pharmaceutical, a nucleating agent, e.g. mica, talc or kaolin, for promoting crystallization of the animal drug may be incorporated with the hydrophobic waxy material to promote the crystallization.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a veterinary drug for oral administration to animals by mixing it with feed, etc., and a method for producing the same.

PRIOR ART AND PROBLEMS Conventionally, oral preparations for animals have been sold in various forms such as powders, fine granules, tablets, granules, pellets, and sugar-coated tablets.

However, these forms of formulations disintegrate due to moisture in the feed, or when mixed in feed and administered to animals, the formulation disintegrates or dissolves in the mouth. Therefore, it is difficult to administer drugs having a bitter taste, and a means to solve this problem is required.

The present inventors have determined that if the oral preparation for animals is made into particles of a certain particle size or less, it will not easily disintegrate when the animal chews the feed, and therefore it will be difficult to disintegrate when the animal chews the feed. It has been found that by coating the drug and reducing the size of the coated particles to 5 mm or less in advance, the bitter taste of the drug can be prevented and oral administration to animals can be facilitated.

As a method for producing such a formulation, the present inventors melt a hydrophobic waxy substance to a temperature above its melting point, dissolve or mix the veterinary drug therein, and then inject this molten mixture into a cold atmosphere. They then found that when the mixture was cooled, the animal drug crystallized and precipitated, and a hydrophobic waxy substance solidified on its surface to form a surface coating, resulting in a granular preparation.

However, depending on the type of veterinary drug and the combination with the waxy substance, it may be difficult to crystallize, the waxy substance may become soft even after crystallization, or a relatively soft waxy substance must be used. In addition, there are some products that require storage at high temperatures or for a fairly long period of time, which can cause problems such as caking due to coagulation of drug particles during storage.

Means for Solving the Problems The present invention solves the above problems by coating the surface of the particulate veterinary drug formulation with a water-soluble polymer. That is, the present invention relates to a veterinary drug preparation in which the surface of a granular veterinary drug preparation coated with a hydrophobic waxy substance is further coated with a water-soluble polymer.

In the present invention, the veterinary drug may be any drug that is solid at room temperature and can be orally administered to animals, but is not particularly limited to the following:
There is no particular need to apply the present invention to drugs that are tasteless and odorless to animals.

Examples of veterinary drugs to which the present invention can be applied include antibiotics, sulfa drugs, nitrofuran drugs, and thiolane compounds such as isobrothiolane.

The waxy substance that is solid at room temperature used in the present invention is used to coat the crystals of the veterinary drug to prevent the drug from dissolving in the mouth. Therefore, animal drugs are hydrophobic substances that are solid at room temperature and melt at a temperature that does not reduce their efficacy when heated.

Hydrophobicity inhibits the dissolution of veterinary drugs in the mouth. The wax-like substance to be used is one that dissolves or mixes the animal drug to be coated when melted and precipitates as crystals when cooled. Furthermore, the wax-like substance used is one that is not harmful to animals, and more preferably one that is digested within the animal body, such as fats and oils. Preferred waxes include higher fatty acids (e.g. palmitic acid, stearic acid, etc.), hydrogenated natural oils (e.g. hardened beef tallow oil), natural waxes (e.g. wood wax), mineral waxes (e.g. paraffin), and synthetic waxes (e.g. higher fatty acids). amide, monoglyceride, etc.). Particularly preferred are waxes with a melting point of 50 to 100°C, such as hardened beef tallow oil,
It is hydrogenated rapeseed oil.

The amount of hydrophobic waxy substance used is 1 part by weight or more, particularly 5 to 50 parts by weight, per 100 parts by weight of the veterinary drug. If too little is used, the coverage with the waxy substance will be uneven.

If the veterinary drug is difficult to crystallize in waxy materials, it may be difficult to obtain granular formulations. Therefore, in such cases, a nucleating agent for promoting the crystallization of the veterinary drug, such as mica, talc, kaolin, titanium oxide, lactose, dextrin, etc., may be added to promote the crystallization of the veterinary drug. . Such a nucleating agent may be added in an amount of 0.01 part by weight or more per 100 parts by weight of the veterinary drug.

The above granular preparation has a diameter of 0.1 to 5 mm, more preferably 1 to 5 mm.
Shape to 2mm. If it is larger than 5 mm, it will crumble and taste bitter when chewed. If it is smaller than 0.1+++m, it is difficult to formulate a formulation.

For example, the above granular preparation can be made by melting a hydrophobic waxy substance, adding a nucleating agent if desired, dissolving or mixing the veterinary drug therein, and spraying this under pressure into a cold atmosphere from a nozzle.
A film of waxy substance forms on the surface of the veterinary drug. The cold atmosphere may be a gas such as air or a liquid such as water. The temperature of the melted mixture during injection is 30
~200°C, and the temperature of the cold atmosphere is preferably room temperature or lower.

The obtained granular veterinary drug preparation can be orally administered to animals as it is, and the bitter taste is suppressed. However, if it is stored at high temperatures or for a long period of time, the waxy substance on the surface softens or becomes sticky due to pressure, resulting in a cake-like appearance. It may become. This tendency is particularly strong for veterinary drugs that are poorly crystallized and those that have soft waxes.

In the present invention, a water-soluble polymer skin is further formed on the surface of this granular preparation. In the case of oil-soluble polymers, there is a risk that they will be plasticized by the wax used in the granular formulation, and their surface protection function will be lost over time.

Water-soluble polymers suitable for the present invention include methylcellulose, cellulose acetate, cellulose phthalate,
Examples include hydroxypropyl methylcellulose, methyl acrylate/methacrylic acid copolymer, and gelatin. - These polymers are used as aqueous solutions. When water is used as a cooling medium when spraying the molten mixture of the veterinary drug and wax, the water-soluble polymer may be dissolved in the water. However, in this method, the formulation particles tend to stick during drying, and special measures are required for drying.

In the present invention, a particularly suitable method for coating the water-soluble polymer is a method using a fluidized bed apparatus (1) as shown in FIG. Particles obtained from animal drugs and a waxy substance are placed on the bed (2) in a fluidized bed, and a fluidized bed is formed by blowing hot air from below through a wind pipe (4) to an extent that does not soften the waxy substance. Send the air at the appropriate air volume. On the other hand, an aqueous polymer solution may be sprayed through a water sprinkler pipe (5) provided at the top of the fluidized bed device (1) and dried to form a polymer film.

Of course, the polymer coating method is not limited to these methods.

The concentration of the water-soluble polymer aqueous solution should be as high as possible as long as the polymer film adheres uniformly.
5000 cps, more preferably 10-500 cps
It is preferable to adjust so that Therefore, as long as the polymer can form a film, it is preferable that the polymer has a low viscosity.

Examples will be described below.

Example 1 900 g of isobrothiolane was added to hydrogenated rapeseed oil (melting point 68°C).
Heated to 80°C with 00g of N. Isobrothiolane and rapeseed hydrogenated oil melted into a homogeneous transparent liquid. l this
The mixture was injected at an injection pressure of 0.5 kg/c11'' from the top of a granulation tower equipped with a nozzle having pores of .

On the other hand, air at 15° C. was flowed countercurrently to the jet flow to cool and harden the jet.

The particle size of the obtained veterinary drug preparation was 1.5 mm on average, and 4
If you store it at 5℃, it will become sticky and will last for 12 days at 40℃! When stored under a pressure of 50 gr/ax'', it solidified into a cake-like shape, and even when it was loosened by hand, it could not be made into complete unit particles.

Take L kg of the above particles, place them on a bed (2) of a fluidized bed apparatus (1) (manufactured by Freund Sangyo Co., Ltd., size: container capacity 2, 50) as shown in Figure 1, and blow air at 40°C from below. Meanwhile, a 5% aqueous solution of hydroxypropyl methyl cellulose (viscosity 20 cps, temperature 25°C) was sprayed from above at a rate of 20 m/min and dried.The obtained veterinary drug preparation of the present invention had an average particle size of 1 , 6 mm,
Its surface was coated with a water-soluble polymer (5.5 parts by weight per 100 crushed parts of veterinary drug in terms of solid content), and this was heated to 40°C.
There was no aggregation of particles even after long-term storage. This was also mixed into feed and given to cows, but they did not spit out the feed.

900g of X-Koi isobrothiolane, hydrogenated rapeseed oil (melting point 680)
°C) 100g and mica powder (particle size distribution 0°5-3.0
μm) Ig was warmed to 80°C. This has a diameter of 0 and 7
It was injected into water at 25°C at a pressure of 4 to 97 cm' using an injector with a mm nozzle. This was further dried in a hot air dryer at 40°C. The average particle size of the obtained formulation was 1
．． It was 5 mm. This was coated with a water-soluble polymer under the same conditions as in Example 1 except that a 5% aqueous solution of methylcellulose (20 cps) was used. The amount of polymer deposited was 5.5 parts by weight per 100 parts by weight of the animal drug. The obtained veterinary drug preparation was mixed into feed and administered to cows, but the animals did not spit out the feed. Further, this preparation was stored at 40° C. for 40 days, but no caking occurred.

Effect of the invention The present invention provides a granular formulation of a veterinary oral drug without bitter taste.

Even when the granular preparation of the present invention is stored at a relatively high temperature for a long period of time, caking due to coagulation of particles does not occur.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a fluidized bed apparatus for coating polymers when producing the veterinary drug formulation of the present invention. In the figure, (1) shows a fluidized bed apparatus, (2) a bed, (3) a wind pipe, and (5) a water pipe. (Figure 1 Procedural amendments issued by Gang) August 20, 1985 Patent Application No. 110831 of 1985 2. Name of the invention Polymer-coated veterinary drug preparation 3. Relationship with the person making the amendment Patent applicant 4. Agent Person 7, Contents of amendment (1) Page 7, line 6 of the specification, "adhesive" should be replaced with "adhesion"
Correct. 2) On page 10, line 8 from the bottom, "1680℃" and "6
Corrected to 8℃. that's all

Claims (1)

[Claims] 1. A veterinary drug preparation in which the surface of a granular veterinary drug preparation coated with a hydrophobic waxy substance is further coated with a water-soluble polymer. 2. The veterinary drug formulation according to item 1, wherein the veterinary drug has a melting point of 30 to 100°C. 3. The veterinary drug formulation according to item 1, wherein the veterinary drug is a thiolane compound. 4. The veterinary drug preparation according to item 1, wherein the hydrophobic waxy substance is a substance that can be mixed with or dissolved in the veterinary drug by melting at a temperature below the decomposition temperature of the veterinary drug. 5. The veterinary drug preparation according to item 1, wherein the granular preparation further contains a nucleating agent for crystallizing the veterinary drug. 6. The veterinary drug preparation according to item 1, wherein the nucleating agent is selected from mica, talc, kaolin, titanium oxide, lactose, and dextrin. 7. The veterinary drug formulation according to item 1, wherein the water-soluble polymer is selected from methylcellulose, cellulose acetate, cellulose phthalate, hydroxypropylmethylcellulose, methyl acrylate/methacrylic acid copolymer, and gelatin. 8. The veterinary drug formulation according to item 1, which contains 1 part by weight or more of a hydrophobic waxy substance and 1 to 500 parts by weight of a water-soluble polymer per 100 parts by weight of the veterinary drug. 9. The veterinary drug formulation according to item 1, having an average particle size of 0.1 to 5 mm.