GB1064582A - Lipid-containing sustained release pharmaceutical compositions - Google Patents

Abstract

Sustained release pharmaceutical compositions for oral administration comprise a homogeneous mixture of one or more drugs with one or more digestible fatty materials, one or more swelling agents, and one or more digestion-resistant waxy materials in a proportion not exceeding 10% of the total weight of the composition. Digestible fatty materials are glyceryl mono- or tri-stearate, or mono- or tri-oleate, stearic or oleic acid, diglycol stearate, or calcium or magnesium stearate. Swelling agents are proteins such as gluten and casein, or cellulose ethers such as methyl cellulose, carboxymethyl cellulose, hydroxyethylcellulose, and their non-toxic metal salts (e.g. sodium). Waxy materials are cetyl alcohol, solid and liquid paraffinic hydrocarbons, or bees wax, carnauba wax, bay berry wax and palm wax. The compositions may be prepared either by melting and mixing the components or dissolving them in a suitable solvent, mixing, and evaporating the solvent. The compositions may be employed in a liquid state as a coating composition, or granulated, optionally with fillers and lubricants, and then formed into tablets, or else the granules may be coated and coloured and filled into capsules, optionally as a mixture of granules having different release rates or containing different drugs. Examples are given for the preparation of amphetamine-containing granules, which are tabletted and also encapsulated.