SummaryAndrogenetic alopecia is the most common hair loss disorder, affecting both men and women. Initial signs of androgenetic alopecia usually develop during teenage years leading to progressive hair loss with a pattern distribution. Moreover, its frequency increases with age and affects up to 80 % Caucasian men and 42 % of women. Patients diagnosed with androgenetic alopecia may undergo significant impairment of quality of life. Despite the high prevalence and the variety of therapeutic options available, there have been no national or international evidencebased guidelines for the treatment of androgenetic alopecia in men and women so far. Therefore, the European Dermatology Forum (EDF) initiated a project to develop an evidence-based S3 guideline for the treatment of androgenetic alopecia. Based on a systematic literature research the efficacy of the currently available therapeutic options was assessed and therapeutic recommendations were passed in a consensus conference. The purpose of the guideline is to provide dermatologists as well as general practitioners with an evidence-based tool for choosing an efficacious and safe therapy for patients with androgenetic alopecia. Keywords• alopecia • androgenetic • Therapy • Guideline • hair loss I Introduction to the guideline Needs/problems and issues in patient careAndrogenetic alopecia (AGA) is a common chronic dermatologic disease, affecting both men and women. It is characterized by progressive hair loss usually occurring in a pattern distribution. The frequency increases with age. In Caucasians, at the age of 70 or beyond 80 % of men and up to 42 % of women have signs of androgenetic alopecia. Though the prevalence is high in elderly patients, androgenetic alopecia often already starts at puberty.Independent of age and gender, patients diagnosed with androgenetic alopecia undergo significant impairment in their quality of life. Hair is an important feature of image. Hair loss affects self-esteem, personal attractiveness and may lead to depression and other negative effects of life [1]. Androgenetic alopecia is clearly a burden for both sexes, but it is substantially more distressing for women [2].

Androgenetic alopecia is the most common hair loss disorder, affecting both men and women. Initial signs of androgenetic alopecia usually develop during teenage years leading to progressive hair loss with a pattern distribution. Moreover, its frequency increases with age and affects up to 80% Caucasian men and 42% of women. Patients afflicted with androgenetic alopecia may undergo significant impairment of quality of life. The European Dermatology Forum (EDF) initiated a project to develop evidence-based guidelines for the treatment of androgenetic alopecia. Based on a systematic literature research the efficacy of the currently available therapeutic options was assessed and therapeutic recommendations were passed in a consensus conference.The purpose of the guideline is to provide dermatologists with an evidence-based tool for choosing an efficacious and safe therapy for patients with androgenetic alopecia.

Androgenetic alopecia (AGA) is the most common hair loss disorder, affecting both men and women. Due to the frequency and the often significant impairment of life perceived by the affected patients, competent advice, diagnosis and treatment is particularly important. As evidence-based guidelines on hair disorders are rare, a European consensus group was constituted to develop guidelines for the diagnostic evaluation and treatment of AGA. This S1 guideline for diagnostic evaluation of AGA in men, women and adolescents reviews the definition of AGA and presents expert opinion-based recommendations for sex-dependent steps in the diagnostic procedure.

Androgenetic alopecia (AGA), or male pattern hair loss, affects approximately 50% of the male population. AGA is an androgen-related condition in genetically predisposed individuals. There is no treatment to completely reverse AGA in advanced stages, but with medical treatment (eg, finasteride, minoxidil, or a combination of both), the progression can be arrested and partly reversed in the majority of patients who have mild to moderate AGA. Combination with hair restoration surgery leads to best results in suitable candidates. Physicians who specialize in male health issues should be familiar with this common condition and all the available approved treatment options.

Alopecia areata (AA) is a nonscarring hair loss disorder with a 2% lifetime risk. Most patients are below 30 years old. Clinical types include patchy AA, AA reticularis, diffuse AA, AA ophiasis, AA sisiapho, and perinevoid AA. Besides scalp and body hair, the eyebrows, eyelashes, and nails can be affected. The disorder may be circumscribed, total (scalp hair loss), and universal (loss of all hairs). Atopy, autoimmune thyroid disease, and vitiligo are more commonly associated. The course of the disease is unpredictable. However, early, long-lasting, and severe cases have a less favorable prognosis. The clinical diagnosis is made by the aspect of hairless patches with a normal skin and preserved follicular ostia. Exclamations mark hairs and a positive pull test signal activity. Dermoscopy may reveal yellow dots. White hairs may be spared; initial regrowth may also be nonpigmented. The differential diagnosis includes trichotillomania, scarring alopecia, and other nonscarring hair loss disorders such as tinea capitis and syphilis.