Isotretinoin is indicated for the treatment of severe recalcitrant nodular acne. Nodules are inflammatory lesions with a diameter of 5 mm or greater. The nodules may become suppurative or hemorrhagic. Because of significant adverse effects associated with its use, Isotretinoin should be reserved for patients with severe nodular acne who are unresponsive to conventional therapy, including systemic antibiotics. In addition, Isotretinoin is indicated only for those female patients who are not pregnant, because Isotretinoin can cause severe birth defects