Liposomes: a drug carrier system for topical treatment in dermatology

During the last three decades, the value of liposomes as a drug delivery system has been examined. The interest in liposomes as carriers of active substances is based on their potential to enclose various types of biological materials and to deliver them to diverse cell types. Whereas experiments with systemically applied liposome-entrapped drugs often proved disappointing, recent work suggests that liposomes as vehicles for topical drug delivery may be superior to conventional preparations. The use of liposomes in ophthalmology for the diagnosis and treatment of different ocular diseases has been postulated recently. Dermatics based on liposomes as drug carrier systems have been tested for different types of ingredients, e.g., corticosteroids and local anesthetics. To understand more about the pharmacological potential of liposomes, it is important to investigate the interaction between liposomes and the epidermis. Analysis in this field suggests that only a compromised epidermal barrier enables intact liposomes to penetrate the skin. This is in accordance with clinical findings. A liposomal preparation of betamethasone dipropionate seems superior to a conventional commercial preparation in eczema but not in psoriasis vulgaris. However, one cannot rule out the follicular pathway as an alternate route. Many questions must be resolved before a complete understanding of liposomes as a drug carrier system in dermatology can be reached. However, examinations performed so far indicate that liposomes might be useful as vehicles for topical drug delivery in various diseases of the skin.