Controlled release tablet

Claim 2

A controlled release tablet comprising (I) a core, containing as essential components (a1) at least one water-soluble pharmaceutically active substance; (a2) a water-insoluble, non-digestible polymeric excipient being a member of the group consisting of (i) polyvinylchloride and (ii) a homo- or copolymer of lower alkyl acrylates, lower alkyl methacrylates, or lower alkyl acrylate and lower alkyl methacrylate; and (b) a water-insoluble polymeric substance which is swellable under the influence of water being a member of the group consisting of hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, carboxymethylcellulose, sodium carboxymethylcellulose, alginic acid, sodium alginate, and cellulose, and (II) a coating consisting essentially of an elastic, water-insoluble and semipermeable diffusion film of a polymer.

Claim 3

A controlled release tablet comprising (I) a core, containing as essential components (a1) at least one water-soluble pharmaceutically active substance; (a2) a water-insoluble, non-digestible polymeric excipient being a member of the group consisting of (i) polyvinylchloride and (ii) a homo- or copolymer of lower alkyl acrylates, lower alkyl methacrylates, or lower alkyl acrylate and lower alkyl methacrylate; and (b) a water-insoluble polymeric substance which is swellable under the influence of water being a member of the group consisting of hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, carboxymethylcellulose, sodium carboxymethylcellulose, alginic acid, sodium alginate, and cellulose, and (II) a coating consisting essentially of an elastic, water-insoluble and semipermeable diffusion film of an ethyl acrylate/methyl methacrylate copolymer.

Claim 4

A controlled release tablet comprising (I) a core, containing as essential components (a1) at least one water-soluble pharmaceutically active substance; (a2) a water-insoluble, non-digestible polymeric excipient being a member of the group consisting of (i) polyvinylchloride and (ii) a homo- or copolymer of lower alkyl acrylates, lower alkyl methacrylates, or lower alkyl acrylate and lower alkyl methacrylate; and (b) a water-insoluble polymeric substance which is swellable under the influence of water being a member of the group consisting of hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, carboxymethylcellulose, sodium carboxymethylcellulose, alginic acid, sodium alginate, and cellulose, and (II) a coating consisting essentially of an elastic, water-insoluble and semipermeable diffusion film of an ethyl acrylate/methyl methacrylate copolymer.

Claim 5

The controlled release tablet according to claim 2, wherein said water-soluble pharmaceutially active substance, or one of them, is a member of the group consisting of potassium chloride, lithium salts, non-steroidal antiinflamatory drugs, calcium salts, mixtures of methyl-xanthines, sodium fluoride and O-β-hydroxyethylated rutins.

Claim 6

The controlled release tablet according to claim 17, in which the water-insoluble, non-digestible polymeric excipient is an ethylacrylate/methyl methacrylate copolymer.

Claim 7

The controlled tablet according to claim 17, in which the water-insoluble polymeric substance which is swellable under the influence of water is cellulose in microcrystalline form.

Claim 8

The controlled release tablet according to claim 1, wherein the water-soluble pharmaceutically active substance, or one of them, is a member of the group consistng of potassium chloride, lithium salts, non-steroidal antiinflammatory drugs, calcium salts, mixtures of methyl-xanthines, sodium fluoride and O-β-hydroxyethylated rutins.

Claim 9

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is potassium chloride.

Claim 10

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is a lithium salt.

Claim 11

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is ibuprofen.

Claim 12

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is pirprofen.

Claim 13

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is a calcium salt.

Claim 14

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is sodium fluoride.

Claim 15

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is a mixture of methyl-xanthines.

Claim 16

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is a mixture of proxyphylline, diprophylline and theophylline.

Claim 17

The controlled release tablet according to claim 1, characterised in that the water-soluble pharmaceutically active substance is a mixture of O-β-hydroxyethylated rutins.