Dithranol

Anthralin (1,8‐dihydroxy‐9anthrone, dithranol) is an older anti-psoriatic agent that was first synthesized as a derivative of chrysarobin, obtained from the araroba tree in Brazil over 100 years ago. Adverse effects of anthralin include irritation and discoloration of the skin [A27277]. This specific property of the molecule inspired workers to study details of its pharmacology. It is important to consider that the drug is relatively innocuous, yet effective, and systemic side effects have not been observed with this anthralin, in contrast to a wide variety of systemic and topical therapies for psoriasis [L1935]. Anthralin is also known as dithranol. It is a main active ingredient in topical skin formulations for the treatment of psoriasis. Various formulations of the drug are available, including solutions, foams, and shampoos [L1979]. The chemical structure of anthralin allows for dual solubility, permitting the compound to be absorbed well through the epidermis [A27276]. Anthralin has also been studied in the treatment of warts, showing promising results [A32307]. Salicylic acid is frequently added to anthralin to augment the stability of anthralin and to increase its penetration and efficacy [L1979].