Granular sustained release preparation and production thereof

1. A non-coated, sustained release pharmaceutical composition consisting of a plurality of granules, the granules consisting of:

(i) about 10% to about 60% by weight of a non-coated complex particulate comprising an ion consisting of a styrene-divinylbenzene sulfonic acid cationic exchange resin and a pharmaceutically active material complexed with the ion exchange resin, the pharmaceutically active material being selected from the group consisting of oxycodone hydrochloride, tramadol hydrochloride, dextromethorphan, hydrocodone bitartrate, chlorpheniramine maleate, codeine, morphine or morphine salt, hydrocodone, phenylpropanolamine, pseudoephedrine, dihydrocodeine, methylephedrine, ephedrin, paraamino salicylic acid, phentermine, pilocarpine, metoclopramide and theophylline; and,

(ii) a non-coated, granulated water-insoluble matrix consisting of microcrystalline cellulose,

wherein the non-coated, complex particulate is embedded into the non-coated, granulated water-insoluble matrix of microcrystalline cellulose, and further wherein the non-coated, granulated water-insoluble matrix of microcrystalline cellulose sustains release of the pharmaceutically active material from the non-coated, complex particulate.

2. The non-coated composition of claim 1 wherein the initial resin particle size is in the range of US Std. Mesh sizes from about #10 to about #400.

3. The non-coated composition of claim 1 wherein the pharmaceutically active material is hydrocodone bitartrate.

4. The non-coated composition of claim 1 wherein the pharmaceutically active material is chlorpheniramine maleate.

5. The non-coated composition of claim 1 wherein the non-coated, granulated water-insoluble matrix of microcrystalline cellulose sustains release of the pharmaceutically active material from the complex particulate for about 8 hours.

6. The non-coated composition of claim 5 wherein the non-coated, granulated water-insoluble matrix of microcrystalline cellulose sustains release of the pharmaceutically active material from the complex particulate for about 8 hours when granules of the non-coated composition are placed in a 0.1 N HCl solution and agitated at 100 rpm.

7. The non-coated composition of claim 1 wherein the granules consist of about 10% to about 50% by weight of the non-coated complex particulate.

8. The non-coated composition of claim 1 wherein the microcrystalline cellulose has a nominal mean particle size of from about 20 to about 180 microns.