GB837451A - Sustained release therapeutic composition and process of preparing same - Google Patents

Abstract

A tablet to maintain a sustained release of medicament in the presence of body fluids is made from a mixture of medicament-containing granules dispersed in a medicament-free matrix, each granule consisting essentially of a mixture of a medicament and excipients consisting of a binder, a swelling agent, a hydrophobic compound solid at body temperatures and being an aluminium or alkaline-earth metal salt of higher fatty acids or a mineral wax or animal or vegetable fat and a hydrophilic compound solid at body temperatures being higher fatty acid partial esters of glycerol and propylene glycol: the matrix consisting of a mixture of equal amounts of a hydrophobic compound (as above) and an alkaline water-soluble salt of ammonium, sodium or potassium, such as trisodium phosphate. The binder may be zein or ethyl cellulose; the swelling agent may be guar gum, gum tragacanth, carboxymethyl cellulose or its sodium or potassium salts or natural clays such as bentonite. In the specific example the medicament is phenobarbitol.