Isotretinoin is the strongest, most effective oral treatment for patients with severe acne vulgaris, with remission rates of 89% and higher. Because of its potency, isotretinoin causes many adverse reactions. This article reviews common and severe adverse reactions to isotretinoin and how providers can best manage these reactions. Because of inconclusive research on the correlation between isotretinoin and depression and irritable bowel syndrome, providers should ask patients about symptoms monthly. Prescribing micronized isotretinoin and starting at the lowest dose with gradual upward titration also can help reduce the incidence of adverse reactions.