Formulation, bioavailability and pharmacokinetics of rectal administration of lorazepam suppositories and comparison with oral solution in Mongrel dog

Abstract

Suppositories were formulated from fatty bases (cocoa butter containing sodium lauryl sulphate and Tween 80) and water soluble bases (from different compositions of PEGs). Their physical properties and bioavailability of the drug in the Mongrel dogs through rectal route were studied. The rectal absorption of the drug from suppositories of all the batches was compared with the oral solution. Suppositories of all the batches exhibited the slower rate and lesser extent of bioavailability except the batch PEGL-3 which showed the slower rate yet the same extent (p > 0.05) of bioavailability as compared to oral solution.