Propylene glycol in the treatment of seborrheic dermatitis of the scalp: a double-blind study.

Thirty-nine patients with seborrheic dermatitis of the scalp were treated in a double-blind controlled study with a solution containing either 15 percent propylene glycol, 50 percent ethanol, and 35 percent water, or a solution containing 50 percent ethanol and 50 percent water. Two patients did not return for follow-up. Sixteen of eighteen (89 percent) in the group treated with propylene glycol showed healing, compared to six of nineteen (32 percent) in the other group. In twenty patients quantitative cultures for Pityrosporum orbiculare were taken. The number of organisms was reduced significantly after treatment with the propylene-glycol-containing solution but not in the other group. This propylene-glycol-containing solution was easy to apply, cosmetically attractive, and may be an alternative to corticosteroids for the treatment of seborrheic dermatitis of the scalp.