Hair loss. It may be localised or total. The commonest type, which is hereditary, is male baldness (androgenic alopecia). Female balding spares the anterior hair line, develops later, and is less severe than the male variety. Diffuse, sudden and rapid hair loss sometimes occurs after childbirth, severe illness or infection (telogen alopecia); it begins 8–12 weeks after the causative event and recovery is complete in most cases, but the condition is permanent in a few. Persistent diffuse hair loss may be caused by severe iron deficiency or HYPOTHYROIDISM, or may be drug-induced.
Patchy localised hair loss is commonly caused by fungal infections (tinea capitis – see RINGWORM), especially in the tropics. It may also be due to trauma, such as hair-pulling by children (trichotillomania) or disturbed adults, or hair-straightening by African or Afro-Caribbean women (traction alopecia). Rarely, diseases of the scalp such as discoid lupus erythematosus (see under LUPUS) or lichen planus (see under LICHEN) may cause patchy alopecia with scarring which is irreversible. The long-term effects of radiotherapy may be similar.
depends on the cause. Certain antifungal drugs cure tinea capitis. Correction of thyroid or iron deficiency is effective but only when those deficiencies are the underlying cause. Male baldness may be modified somewhat by long-term use of minoxidil lotion, or improved permanently by various types of hair-follicle grafting of transplants from the occipital scalp. Female balding is sometimes helped by treatment with anti-androgen/oestrogen medication.
An absence of hair from areas of the skin on which it normally grows. The loss of hair with ageing in men is largely hereditary. In women,...
typical hereditary baldness in the male characterized by loss of hair on the crown and temples :androgenetic alopecia in men