Androgenetic Alopecia: a Review and Emerging Treatments

Abstract

Androgenetic Alopecia (AGA) is the most common noncicatricial alopecia that leads to the progressive miniaturization of the hair follicle. Scalp terminal hairs are converted into vellus hairs, primarily due to two factors: genetic predisposition and hormonal stimulation.The incidence and prevalence of AGA increases with age. The onset of AGA is gradual, and when this pathology progresses, the anagen phase shortens and the telogen phase remains constant. The shedding area varies from patient to patient and is usually most marked at the vertex in men, while women with AGA generally lose hair diffusely over the crown.Topical minoxidil and oral finasteride (5-alpha-reductase type II inhibitor) are the gold-standard therapies for AGA and are currently the only Food and Drug Administration (FDA)-approved drugs for the treatment of AGA.The currently available treatments for AGA are sometimes perceived as having limited effectiveness; therefore, the identification of new therapies for this pathology is of utmost importance.This article aims to review the pathogenesis, diagnosis of AGA and all the new emerging treatments for this entity in order to prevent its progression and improve the results of this pathology.

Update Treatment of Male Androgenetic Alopecia

“…3 The interior of the hair bulb is invaginated at the base of the dermal papillae. 6 Hair grows with a continuous cyclic pattern in three phases, namely the anagen, catagen, and telogen that last for 2-6 years, 1-2 weeks, and 5-6 weeks, respectively, and they are exogenous. A normal hair cycle causes hair replacement on the scalp every 3-5 years.…”

“…A normal hair cycle causes hair replacement on the scalp every 3-5 years. 3,6 Hair follicle growth stops and enters the physiological involution stage of transition or the catagen phase when active growth ends. In the catagen phase, the bulbar portion of the follicle is degraded, but the hair follicle stem cells remain in the bulge.…”

“…After that, the follicles undergo apoptosis and enter the telogen phase. 6 Based on the pathogenesis of MAGA, androgens are the main hormones involved in the interaction of the papillae of the dermis and hair follicles in the miniaturization of hair follicles. Two androgen hormones involved are testosterone and 5dihydrotestosterone (DHT).…”

Assessment of Serum Vit D and Serum Ferritin in Female Pattern Androgenic Alopecia

“…This allows staging the degree of alopecia at the time of diagnosis and control the evolution and response to the treatment. For male pattern hair loss, the classification widely used is: (1) -Hamilton-Norwood Classification: the most widely classification used for MPHL. (8) There are seven stages of evolution, involving the fronto-temporal area and evolution of hair loss to the vertex.…”

“…Is the most frequent type of hair loss in both sexes. (1) Epidemiology: The onset of AGA is usually gradual and the condition slowly develops over the years. The frequency and severity of this type of hair loss increases with age (4) .…”