Hair physiology and its disorders

Abstract

Hair follicles are complex skin appendages, the perturbations of which have an impact on human health and emotional welfare disproportionate to their small dimensions. Changes to the parameters of hair follicle size, numbers per unit area of skin, and growth cycle time duration determine hair coverage and fundamentally underlie the diagnosis of an individual with alopecia or hypertrichosis. Here we review the hair follicle's physiology, its disorders and principles of hair disorder treatment development. © 2008 Elsevier Ltd. All rights reserved.