Medical Health Encyclopedia

Accutane, more commonly used to treat acne, is generally far less potent than acitretin, but may still be effective against pustular psoriasis and also be effective with phototherapy. An older agent, etretinate (Tegison) was very effective but produced severe side effects and has been withdrawn from the market. It still may be useful for HIV patients.

Benefits. Oral retinoids have the following beneficial properties for patients with psoriasis:

• They have anti-inflammatory actions.
• They help regulate cell reproduction.
• They may even improve arthritis that accompanies psoriasis.

Combinations. Acitretin may be most effective in combination with other agents, usually topical agents and especially with phototherapy. The drug results in faster and more complete responses to PUVA and UBV treatments. Acitretin and phototherapy, in fact, have some of the highest clearance rates of any treatment. Furthermore, lower radiation doses can be used, which may decrease the risk of skin cancers, and some research suggests that retinoids may temporarily suppress the development of these malignancies. Combination therapy also allows lower doses of oral retinoids to be used, which diminishes many skin and mucous membrane side effects. In addition to combination treatments, some experts recommend the following to reduce the toxic effects of acitretin:

• Maintenance doses should be as low as possible and should be taken every second or third day.
• Patients should eat a low-fat diet and get daily aerobic exercise to maintain healthy triglyceride levels.

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Side Effects. All retinoids have the same potentially serious toxicities as do high doses of vitamin A:

• Of special note, retinoids pose a significant risk for birth defects when taken by pregnant women. Children and women who wish to bear children should not take these agents.
• Skin and mucous membrane problems are common. These include dry nose, nosebleeds, dry eyes, chapped lips, thinning hair, dry or "sticky" feeling skin, and peeling of the palms and soles. Nail problems may also develop. Studies on isotretinoin indicate that many of these side effects may be relieved with vitamin E supplements (800 IU daily), but studies on acitretin have not been done.
• Bone and joint pain, fatigue, bruising, and headaches may also occur.
• The drugs may cause eye problems, including blurred vision, cataracts, conjunctivitis, and a sudden deterioration in night vision.
• Retinoids carry a high risk for increased bone growth, particularly in the ankles, pelvic area, and knees.
• They increase levels of triglycerides, which are lipids (fatty molecules in the blood) that are proving to be danger for the heart. Certain cholesterol-lowering agents, including gemfibrozil (Lopid) or statins, such as atorvastatin (Lipitor), may prevent this.
• In rare cases, retinoids, particularly isotretinoin, may cause a condition called benign intracranial hypertension (pseudotumor cerebri), which occurs in the brain. Symptoms include headache, nausea, vomiting, and blurred vision. Patients experiencing these symptoms should call a doctor immediately and stop taking the drug.
• The drugs also can cause damage to the liver, so patients should be monitored regularly.
• Isotretinoin has been associated with depression and possible risk for suicide in some people.