Multiple dose in vivo evaluation of an oral controlled release capsule of theophylline containing film coated mini-tablets in beagle dogs

Abstract

Controlled release capsules containing mini-tablets of theophylline 200 mg, film coated with Eudragit RL 2% w/w were administered orally every 12 h to beagle dogs over a period of 4 days. Parallel single-dose studies were also carried out using the test capsule, a standard marketed product (Theo-Dur 200 mg) and a capsule containing 200 mg of theophylline anhydrous powder. The pharmacokinetic parameters such as area under the curve (AUC), extent of bioavailability (EBA) and dosage form index (DI) were calculated and compared. Results show that the absorption from the test capsule was maximal and when compared to Theo-Dur the test capsule had a greater EBA (1.09 for the test capsule and 0.74 for Theo-Dur). Dosage titration can be made more precise with this multiple unit sustained release theophylline preparation for the particular needs of the patient.