Retinol side effects

Must /3-caroteiie is converted to retinol during absorption, but the fraction that is absorbed is distributed widely and accumulates in the skin. The metabolic pathway of /3-carotene is similar to that of retinol. Several weeks of therapy are required before enough accumulates in the skin to exert protective effects. Carotenrxlermiu. a result of accumulation in the skin, is the major side effect. A tanning" capsule containing Carotene attd canthaxanthin. however. u.ses this effect. 

Retinoids include natural compounds and synthetic derivatives of retinol that exhibit vitamin A activity. Retinoids have many important functions throughout the body, including roles in vision, regulation of cell proliferation and differentiation, and bone growth, immune defense, and tumor suppression. Because vitamin A affects normal epithelial differentiation, it was investigated as a treatment for cutaneous disorders but was abandoned initially because of unfavorable side effects. Molecular modifications yielded compounds with vastly improved margins of safety. 

The resurgence of interest in the use of retinoids as therapeutic agents may be traced in large part to the development of new synthetic retinoids that retain efficacy but are generally less toxic than retinol. However, as is evident from the preceding discussion, the newer retinoids are not completely free of potentially serious side effects. 

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