Description: An oral retinoid effective in the treatment of psoriasis. It is the major metabolite of etretinate with the advantage of a much shorter half-life when compared with etretinate. Indication : For the treatment of severe psoriasis in adults. Mechanism of action : The mechanism of action of acitretin is unknown, however it is believed to work by targeting specific receptors (retinoid receptors such as RXR and RAR) in the skin which help normalize the growth cycle of skin cells. Half life : 49 hours (range 33 to 96 hours) Dosage : The recommended dose is 25 to 50 mg per day, given as a single dose with the main meal.