[Retinoids in dermatology]

Retinoids are natural substances, similar to vitamin A, and acting through nuclear receptor on the gene transcription, with a similar mechanism to steroid hormones. Synthetic retinoids are used in the treatment of different skin diseases including severe acne, abnormal keratinization, psoriasis, epidermoid carcinoma, and inflammatory skin lesions. Systemic or local administration of these compounds acts on the proliferation and differentiation of the skin structure by not clearly understood pathway. This pathway could be either an agonist, antagonist or substitutive modulation of the natural retinoid action or a separate pathway. The different drugs have in common, teratogenic properties, which limit their usefulness.