Design for rectal administration of verapamil hydrochloride

ABSTRACT

Verapamil hydrochloride, formulated in rectal suppository dosage from different suppository bases, were used. The permeation of the drug through standard cellophane membrane and its dissolution in aqueous medium from the different formulations were performed at 37C. The water soluble base, polyethylene glycol showed the highest release of the drug. The drug release characteristics indicated adherence to first order kinetics mechanism. In vivo rabbit studies of two suppository formulations compared with intravenous and oral doses were performed. The rectal administration of verapamil hydrochloride in suppositories resulted in a more rapid onset and more intense depressor responses than the oral route