Theophylline sustained-release dosage forms

Very limited drug absorption due to the lack of microvilli and the more viscous and semisolid nature of the lumen contents. A few drugs such as theophylline and metoprolol are absorbed in this region. Drugs that are absorbed well in this region are good candidates for an oral sustained-release dosage form... 

Sagara, K. Kawata, M. Mizuta, H. Shibata, M. Utility of gastrointestinal physiology regulated-dogs Bioavailability study of a commercial sustained-release dosage form of theophylline. Biol. Pharm. Bull. 1994,17 (7), 931-934. 

A dosage interval of 12 h appears to be appropriate to use in dogs for oral sustained-release anhydrous theophylline tablets (Koritz et al, 1986) and oral sustained-release morphine sulphate tablets (Dohoo et al, 1994). Following oral administration of these sustained-release dosage forms, the average systemic availability of theophylline is 76% and of morphine is 21%. Gastro-... 

Ingestion of sustained-release products is the most common route of both accidental and intentional exposure to theophylline. Theophylline is available in oral and intravenous dosage forms. Aminophylline is available in oral, rectal, and intravenous dosage forms. 

Gonzalez Straughn AB. Effect of meals and dosage-form modification on theophylline bioavailability from a 24-hour sustained-release delivery system. CUn Ther (1994) 16, 804-14. 

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