What are the clinical indications for oral isotretinoin?

Oral isotretinoin is FDA-approved for the treatment of severe recalcitrant cystic or nodular acne vulgaris and disorders of keratinization. It is the most effective form of therapy for acne vulgaris; however, it is not a first-line drug and should be reserved for patients with cystic acne who are not responsive to conventional therapies such as oral antibiotics. Isotretinoin produces wide-ranging biologic effects and is used in many other diseases. Many authorities consider it to be the drug of choice for pityriasis rubra pilaris, severe lichen planus, Darier’s disease, and the ichthyoses. A partial list of clinical indications is presented
in Table 56-3.

Table 56-3. Therapeutic Applications of Oral Tretinoin
	FDA-APPROVED INDICATIONS		SELECTED NONAPPROVED APPLICATIONS
	Severe recalcitrant acne vulgaris		Dissecting cellulitis of the scalp Hidradenitis suppurativa Ichthyoses Keratosis follicularis (Darier’s disease) Lichen planus Lupus erythematosus, cutaneous Mycosis fungoides (cutaneous T-cell lymphoma) Nevoid basal cell carcinoma—prevention of basal cell carcinomas Pityriasis rubra pilaris Rosacea Xeroderma pigmentosum—prevention of skin cancers