ABSTRACT
The aim of our studies was to utilize liposomes: (a) as drug carriers to enhance tissue penetration; (b) as drug localizers to minimize drug clearance from the site of action; and (c) as a slow release vehicle to provide prolonged action.
Results of biodisposition studies in rabbits and guinea pigs indicated that most liposomal formulations in multiple-dose topical treatment provided higher drug (triamcinolone, progesterone, econazole, minoxidil, retinoids and local anesthetics) concentration in the skin, than the conventional (ointment, cream gel or lotion) dosage forms. Certain liposomal formulations greatly enhanced both dermal and transdermal drug delivery. With appropriate formulation, targeting the drug even within the skin could be achieved.
Pharmacokinetic, pharmacodynamic and electron microscopic investigation indicated that liposomes carry the encapsulated drug to various layers of the skin and, depending on the type and composition of the liposomal products, they may reduce or increase the cutaneous clearance.
