Formulation of Once- and Twice-daily Theophylline Matrix Tablets using Cissus Populnea Polymer
Musa A. Ibrahim a and Vernon H. Dawes b
Department of Pharmaceutics and Pharmaceutical Technology, University of Jos a , Jos (Nigeria), and Chelsea Pharmacy Department, Kingâs College, University of London b , London (England)
Cissus Populnea Polymer (CPP), a polysaccharide hydrocolloid (similar to agar and tragacanth) obtained from the stem bark of the plant Cissus populnea of the family Amplidaceae (Vitaceae), was used as a novel matrix former for formulating once- and twice-daily theophylline tablets. ANOVA conducted on the effects of different in vitro dissolution variables show that changes in pH, ionic strength and surfactant concentration did not have significant influences on theophylline release. Agitation speed showed a significant influence on the twice-daily product, but not on the once-daily product. Both exhibited zero-order release kinetics for most of the study conditions as shown by the correlation coefficients of the release models considered. The use of computer simulation revealed a satisfactory pharmacokinetic performance of both products, devoid of spike plasma levels and peak-trough variations in the multiple dosing of the products. The products therefore have a good chance of performing satisfactorily in vivo, capable of withstanding the variations of the gastro-intestinal tract conditions of patients, that would enhance patient compliance.
Key words Cissus populnea polymer Â· Matrix tablets Â· Once-daily tablets Â· Theophylline Â· Twice-daily tablets
pharmind 2000, Nr. 3, Seite 243