Doubts concerning the action of hair cosmetics and the health of both body and hair are more frequent in the dermatological visits. Dermatologists need no only to enrich the knowledge of scalp diseases but also of molecular interactions of cosmetics used in hair fi ber, including the infl uence of such products when absorbed by the epithelium of the scalp. The amount of medical visits increases every day to fi nd out which techniques and chemical products are best indicated to enable the desired changes in hair from its natural appearance and, at the same time, to keep the hair healthy and beautiful. In this article, divided in two parts, we discuss the hair physiology, structure and chemical nature, as well as the agents used for its smoothing, coloring, hygiene and cosmetic treatment, and the consequences that such procedures can have on overall health, including their use safety during pregnancy and lactation.

Keywords: HAIR PREPARATIONS, HAIR, HAIR DYES

The trichogram is an easy and semi-invasive method, useful for evaluating different types of hair loss in daily practice. To date, there is no standardized methodology on how to collect and perform the exam. The use of a liquid interface between the slide and the coverslip to read the trichogram under optical microscopy varies widely in the literature. Among the alternatives, transparent enamel base coat is an inexpensive, accessible, and practical option, providing the examiner with proper visualization of the hair shafts with minimal air bubbles formation.

Keywords: Alopecia; Hair diseases; Scalp dermatoses

Although little reported in daily practice, the use of systemic retinoids can cause changes in the shape, color, and texture of hair shafts. We report a case of a patient treated with isotretinoin for acne vulgaris who experienced new growing curly hair. Such hair changes are recognized during therapy with oral retinoids; however, isotretinoin-induced modifications on the hair fiber curvature are extremely rare.

Keywords: Hair; Isotretinoin; Pharmacological treatment

Anagen effluvium (AE) is a hair growth disorder that occurs due to a disturbance in the hair follicle cycling. The most common cause of AE is alopecia areata (AA). Autoimmune diseases like AA may develop after drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome and are usually long-standing conditions. We report the case of a 17-year-old woman who developed a severe and abrupt AE after DRESS syndrome with a full and rapid recovery after two months of topical minoxidil.

Keywords: Alopecia; Alopecia Areata; Drug Hypersensitivity Syndrome; Case Reports