Male pattern alopecia, or androgenetic alopecia, refers to the common patterned hair loss affecting many men and some women. Male pattern alopecia is mediated by dihydrotestosterone, the potent form of testosterone, which induces miniaturization of androgen-sensitive hair follicles. There is a gradual conversion of terminal hairs into indeterminate and finally vellus hairs. The condition may profoundly affect self-esteem and impair psychosocial functioning for some men, and an association between early onset male pattern alopecia and coronary artery disease has been shown. The hair loss has a strong genetic basis. The incidence is highest in White men, followed by Asian men and Black men. The onset is usually prior to age 40.
ICD10CM: L64.9 – Androgenic alopecia, unspecified
SNOMEDCT: 87872006 – Male pattern alopecia
Differential Diagnosis & Pitfalls
Other causes of nonscarring alopecia should be considered if the hair loss does not fit the typical frontal / temporal or vertex pattern of hair loss.