On Dec. 9, 1995, the U.S. Food and Drug Administration (FDA) approved tretinoin, a differentiating agent related to vitamin A, for use in the treatment of acute promyelocytic leukemia. Tretinoin is also known as all-trans retinoic acid (ATRA).

Topical tretinoin has been approved for use in dermatology for 40 years and is currently approved for the treatment of acne vulgaris and photodamage. During this time, topical tretinoin has accumulated significant efficacy and safety data in the treatment of acne and photodamaged skin and demonstrated clinical potential for treating a range of other dermatologic conditions.

The diverse effects may be due to complex underlying mechanisms of action associated with tretinoin, including keratolytic activity, collagenesis, and other mechanisms associated with the activation of nuclear retinoic acid receptors (RARα, RARβ, and RARγ).