Alopecia may be divided into scarring (destruction of hair follicle) and non-scarring (preservation of hair follicle)

Scarring alopecia

• trauma, burns
• radiotherapy
• lichen planus
• discoid lupus
• tinea capitis ^
  • ^ scarring may develop in untreated tinea capitis if a kerion develops

Non-scarring alopecia

• male-pattern baldness
• drugs: cytotoxic drugs, carbimazole, heparin, oral contraceptive pill, colchicine
• nutritional: iron and zinc deficiency
• autoimmune: alopecia areata
• telogen effluvium
  • hair loss following stressful period e.g. surgery
• trichotillomania

Alopecia Areata

Alopecia areata is a presumed autoimmune condition causing localised, well demarcated patches of hair loss. At the edge of the hair loss, there may be small, broken 'exclamation mark' hairs

Hair will regrow in 50% of patients by 1 year, and in 80-90% eventually. Careful explanation is therefore sufficient in many patients.

Neither the British Association of Dermatologists or Clinical Knowledge Summaries recommend screening for autoimmune disease.

Other treatment options include: