Oral retinoid therapy is associated with significant mucocutaneous and systemic toxicity similar to that found in hypervitaminosis A. Beside the well-known mucocutaneous adverse effects like cheilitis, xerosis, desquamation, dryness of mucous membranes, more troublesome findings are ocular effects, hair loss or hypergranulation tissue. The most unwanted systemic side effects under both retinoids (isotretinoin and etretinate) are teratogenicity, bone toxicity and serum lipid increments. Careful patient counselling and monitoring will enable the physician to modulate these effects and reduce their impact on patient compliance.