Reversible hyperpigmentation of skin and nails with white hair due to vitamin B12 deficiency.

A case of reversible generalized hyperpigmentation of the skin and nails with reversible premature gray hair due to vitamin B12 deficiency is reported. The cause of the vitamin B12 deficiency in this patient was pernicious anemia. The pigmentation of his skin and hair returned to normal after treatment with intramuscular cyanocobalamin.