Retinoids are potent, effective, and versatile therapeutic agents. They ameliorate chronic diseases, such as the inherited disorders of keratinization; they virtually cure nodulocystic acne; and they may well prevent some epithelial tumors of the skin and genitourinary tract. They are also toxic. Much is known about the biologic and biochemical effects of retinoids, yet very little is known about their basic mechanisms of action. Therefore, knowledge of their clinical efficacy and toxicity is based largely on empiricism and careful observation.
Retinoids are reliably effective treatment for some diseases yet are only sporadically effective for others. Early investigations with vitamin A led to the expectation that synthetic retinoids would be effective therapy for acneiform eruptions and inherited disorders of keratinization. As anticipated, isotretinoin had a predictably beneficial effect on nodulocystic acne and autosomal recessive (lamellar) ichthyosis. Further clinical experience with isotretinoin yielded some surprising results. Nodulocystic acne not only improved after a course of therapy but also
Milstone LM. Prescribing RetinoidsThe Art and the Science. Arch Dermatol. 1986;122(7):761-763. doi:10.1001/archderm.1986.01660190039011