Medicaments having controlled release of the active compound

Pellets of a medicament having controlled release of the active compound and comprising

• (a) a core which contains
• (a1) an active compound of the formula ##STR7## in which R represents nitro or the group ##STR8## in the ortho- or meta-position, R.sup.1 represents alkyl having 1-4 C atoms, which is optionally interrupted by an oxygen in the chain, and
• R.sup.2 represents alkoxy having 1-4 C atoms, or represents the radical ##STR9## or a compound from the group consisting of 3-(4-fluorophenylsulphonamido)-1,2,3,4-tetrahydro-9-carbazole propanoic acid and 2-[4-(2-pyrimidinyl)-1-piperazinyl] butyl]-1,2-benzisothiazol-3(2H)-one, 1,1-dioxide, and
• (a2) an intensive disintegrating agent from the group comprising crosslinked sodium carboxymethylcellulose or sodium starch glycolate, and
• (a3) sodium laurylsulphate as a wetting agent, and
• (a4) PVP as a binder, and
• b) a double layer which controls the release, consisting of
• b1) an outer undigestible water-permeable lacquer layer which essentially consists of an acrylic resin based on a poly(meth)acrylic acid ester having a neutral character or having a low content of quaternary ammonium groups, consisting of a copoly(meth)acrylic acid ester having the structural element ##STR10## wherein R.sup.3 represents H or CH.sub.3 and
• R.sup.4 represents CH.sub.3 or C.sub.2 H.sub.5,
• and having an average molecular weight of about 800,000, and
• the said ester having the low content of quaternary ammonium groups differing in that the R.sup.4, in a molar ratio of 1:20 to 1:40, represents the group ##STR11## and it has an average molecular weight of about 150,000, or consists essentially of ethylcellulose, optionally contains antiadhesive agents, and
• b2) an inner jacket which controls the migration of the water in the direction of the core and consists essentially of about 10 to 40% of hydroxypropylcellulose and about 60 to 90% of a hydrophobic additive selected from the group consisting of calcium stearate and hydrogenated castor oil.