In vitro and in vivo correlation for controlled-release formulation of d-chlorpheniramine maleate.

Four commercial controlled-release tablets of d-chlorpheniramine maleate, which showed various drug release properties, were administered to beagle dogs, and the correlation between in vitro drug release and in vivo absorption was studied. The mean in vivo absorption amount-time profile for each product showed good accordance with the in vitro drug release profile until 2-3 h after administration. However, absorption of the drug in dogs terminated at about 3 h. This short absorption time may be due to a short intestinal residence time for these dosage forms in the dog. In the present study, the deconvolution method was proved to be useful for in vitro/in vivo comparison, which clarified the in vivo absorption of controlled-release dosage forms having various release profiles.