Pharmaceutical composition and process for its preparation
AssigneeGist-Brocades N.V.
InventorsPiet J. Akkerboom, Robert De Cocq, Maria Wegman
Life of this patent
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Abstract
A multi-purpose pharmaceutical tablet which can either be readily swallowed or dissolved in water to give a dispersion, comprising a tetracycline, microcrystalline cellulose or microfine cellulose, low substituted hydroxypropylcellulose and a thickening agent, preferably hydroxypropyl methylcellulose, and optionally other conventional adjuvants. The tablet may be easily swallowed as such, and when immersed in water, it affords a very fine dispersion within 30-60 seconds. The tablet may be prepared by direct compression, or by a wet granulation process in which a granulate is used which contains tetracycline and any substantial amount of a wet binding substance.
Claims24
A pharmaceutical tablet, comprising:
- tetracycline;
- a cellulose produce selected from the group consisting of microcrystalline cellulose, microfine cellulose and mixtures thereof;
- low-substituted hydroxypropylcellulose;
- and
- a thickening agent selected from the group consisting of natural gums and cellulose derivatives, and having a viscosity of less than 50 cps, measured as a 2% by weight aqueous solution at 20.degree. C. wherein the weight ratio of low-substituted hydroxypropylcellulose to the thickening agent is between 3:1 and 10:1, and the cellulose product is present in an amount of 20-60 wt % based on the weight of the tetracycline.
A pharmaceutical tablet, comprising:
- tetracycline;
- a cellulose product selected from the group consisting of microcrystalline cellulose, microfine cellulose and mixtures thereof;
- low-substituted hydroxypropylcellulose;
- and
- a thickening agent selected from the group consisting of natural gums and cellulose derivatives, and having a viscosity of less than 10 cps in a 2% by weight aqueous solution at 20.degree. C.
- wherein the cellulose product is present in an amount of 20-60 wt % based on the weight of the tetracycline, wherein the low-substituted hydroxypropylcellulose and the thickening agent together amount to 10-40 wt % based on the weight of the tetracycline, and the weight ratio of the low-substituted hydroxypropylcellulose to the thickening agent is between 3:1 and 10:1.
A process for the preparation of a pharmaceutical tablet of controlled disintegrating by direct compression, comprising the step of:
- making an intimate mixture of tetracycline;
- a cellulose product selected from the group consisting of microcrystalline cellulose, microfine cellulose and mixtures thereof;
- low-substituted hydroxypropylcellulose;
- and a thickening agent selected from the group consisting of natural gums and cellulose derivatives, and having a viscosity of less than 50 cps, measured as a 2% by weight aqueous solution at 20.degree. C. wherein the weight ratio of low-substituted hydroxypropylcellulose to the thickening agent is between 3:1 and 10:1, and the cellulose product is present in an amount of 20-60 wt % based on the weight of the tetracycline;
- and
- compressing the intimate mixture into tablets.
A process for the preparation by wet granulation of a pharmaceutical tablet comprising tetracycline;
- a cellulose product selected from the group consisting of microcrystalline cellulose, microfine cellulose and mixtures thereof;
- low-substituted hydroxypropylcellulose;
- and a thickening agent selected from the group consisting of natural gums and cellulose derivatives, and having a viscosity of less than 50 cps, measured as a 2% by weight aqueous solution at 20.degree. C. wherein the weight ratio of low-substituted hydroxypropylcellulose to the thickening agent is between 3:1 and 10:1, and the cellulose product is present in an amount of 20-60 wt % based on the weight of the tetracycline, comprising the steps of:
- a) mixing the tetracycline and the cellulose product with water to form a wet mass;
- b) processing the wet mass of step a) to form a granulate;
- c) passing the granulate of step b) through a first woven wire screen;
- d) drying the sieved granulate of step c);
- e) passing the dried granulate of step d) through a second woven wire screen;
- f) collecting the resulting granulate of step e);
- g) mixing the granulate with the low-substituted hydroxypropylcellulose and thickening agent to form an intimate mixture;
- and
- h) compressing the intimate mixture of step g) into tablets.
Dependencies are inferred from the claim text.