Treating Psoriasis With Retinoids

These drugs are related to Vitamin A. They normalize the growth of skin cells in psoriasis. A new retinoid, acitretin (Soriatane) was introduced in 1998, replacing etretinate (Tegison). This drug is useful in treating severe forms of psoriasis, such as Erythrodermic and pustular psoriasis that do not respond to other therapies. Retinoids are almost certain to cause birth defects. They cannot be used by pregnant women, women planning to become pregnant, or their male partners. Women who take acitretin must avoid pregnancy for up to 3 years after they stop taking the drug. Women also must not drink alcohol while they are taking acitretin and for 2 months after they stop taking it. Alcohol can cause the drug to change to its chemical cousin, etretinate, in the blood. Etretinate can cause severe birth defects for many years after its use. Other possible side effects of retinoids are dry skin, chapped lips, dryness of the eyes and nasal passages, hair thinning, sun sensitivity, and bone spurs of the long bones or spine. The drugs may also increase blood levels of liver enzymes and triglycerides, a type of fat found in the blood. Reducing the dose of the drug usually reduces these side effects. Another retinoid, isotretinoin (Accutane) is sometimes used to treat psoriasis. It may be helpful for some people, especially if combined with ultraviolet light treatment, but it is generally less effective than acitretin. Isotretinoin is approved by the U.S. Food and Drug Administration to treat severe acne but not to treat psoriasis.