[Etretinate: pro and con. Risk-benefit analysis of systemic retinoid therapy in psoriasis and recent developments: free aromatic acid, arotinoids].

Synthetic retinoids were first evaluated 15 years ago for systemic treatment of psoriasis in the Federal Republic of Germany. Etretinate was introduced 2 years ago into the market for systemic treatment of all severe types of the disease. Today etretinate is administered as monotherapy and/or combined with other modalities (anthralin, tar, topical corticosteroids, selective UV therapy, RePUVA), which leads to successful clearing in most cases. Nevertheless, thorough consideration of the risk-benefit ratio is required in each individual patient. The advantages and disadvantages are presented that should be taken into consideration. As a rule, severe cases of psoriasis are admitted to the hospital; initial treatment is given and then continued on an outpatient basis. In some patients, particularly those with pustular eruptions and/or erythroderma, low-dosage oral etretinate may be continued for prophylactic reasons over several months or years. Since the amount of hospitalization is reduced, the overall treatment costs are reduced in spite of the high cost of the drug. The main disadvantage of oral retinoids is their teratogenicity, although no severe cases of retinoid toxicity have been reported in the last 2 years in the Federal Republic of Germany since their introduction. As a successor drug to etretinate, its free aromatic acid, Ro 10-1670 is now under clinical investigation. It seems to be clinically effective, is rapidly eliminated, and requires only 4 weeks contraception after discontinuation of oral administration. Arotinoids then follow.