PrefaceThe recent interest in the pharmacology of the skin and the treatment of its diseases has come about for two reasons. The first is a realisation that many aspects of pharmacology can be studied as easily in human skin as in animal models, where they may be more relevant to human physiology and disease. Examples of this are the action of various vasoactive agents and the isolation of mediators of inflammation after UV irradiation and antigen-induced dermatitis. The second reason is the fortuitous realisation that a pharmacological approach to the treatment of skin disease need not always await the full elucidation of aetiology and mechanism. For example, whilst the argument continued unresolved as to whether the pilo-sebaceous infection which constitutes acne was due to a blocked duct or to a simple increase in sebum production, 13-cis retinoic acid, was found quite by chance totally to ablate the disease; again, whilst cyclosporin, fresh from its triumphs in organ transplantation, has been found able to suppress the rash of psoriasis, it has resuscitated the debate on aetiology.We are therefore entering a new era in which the pharmacology and clinical pharmacology of skin are being studied as a fascinating new way of exploring questions of human physiology and pharmacology as well as for the development and study of new drugs, use of which will improve disease control and at the same time help to define pathological mechanisms.It was because of this burgeoning interest in pharmacology of skin and its diseases, that this book came about. Indeed it is long overdue and was planned several years ago; we console ourselves with the thought that the delay may have served to help define certain principles which were then only just emerging.The book is divided into two volumes which are independent but complementary; the first being an account of the general pharmacology of skin, the second volume being more concerned with disease and drugs. The first volume is divided into two parts, the one dealing with the pharmacology of skin systems and their control and the other with autocoids in normal and inflamed skin. This second volume has three parts; the first part deals with the methods of measurement which are becoming of increasing importance both in studying the pharmacological effects of drugs and the clinical pharmacology of skin; the second deals with toxicology in its widest sense -including metabolism and percutaneous absorption; and the third is an account both of specific drugs and the drugs used for specific diseases.