GASTROINTESTINAL DIFFUSION TABLET - INFLUENCE OF POLYOXYETHYLENEGLYCOL-400

The influence of the incorporation of PEG 400 in a cellulose acetate f ilm to control the release of indomethacin or aminophylline was studie d. The aminophylline tablets coated with 20% of PEG 400 and 10 or 20% of diethylphthalate were resistant in purified water if the membrane a mount was higher than 13 mg per tablet. The dissolution rate of indome thacin was very low, 1.3-6.0%. Without PEG in the membrane the dissolu tion rate of aminophylline tablets was slow (6% in 18 h). The increase of the membrane weight (28-41 mg) resulted in a decrease of the disso lution rate with 10 and 20% of diethylphthalate. There was a correlati on between the T-20% and the coating amount for aminophylline. The sol ubility of the drug had a large influence on its dissolution rate. Wit h indomethacin which is poorly soluble, it was difficult to obtain eff icient dissolution with a GDS system using PEG 400.