Isotretinoin is a Vitamin A derivate used for the treatment of severe acne. It is sold by Roche and goes under the trade names Accutane and Roaccutane. It causes foetal malformations and gravidity is strictly forbidden while taking the drug.

Isotretinoin works by reducing the sebacious gland activity amd a histiologically demonstrated reduction of the size of the sebacious glands. The effect is dose and time related.