Alopecia areata and isotretinoin; coincidence or causal relation.

Isotretinoin is a safe and useful medication for acne management. Adverse effects are mostly related to cutaneous and mucous membranes. We present a case of a 24-year-old female patient who was on treatment with isotretinoin for acne vulgaris Grade 4. After 6 months of treatment, the patient presented with localized patch of hair loss. Beginning of alopecia areata in patients with acne vulgaris could be regarded as a side effect of retinoids due to anti-acne therapy. The exact mechanism by which retinoids cause hair loss is not known.