Are there any retinoids found in topical over-the-counter (OTC) products?

Yes. Numerous OTC topical products, especially antiwrinkle and skin rejunvenation products, contain retinol or, less commonly, retinyl palmitate or retinaldehyde. These OTC retinoids do not bind to retinoid receptors and do not exert a biologic effect until they have been enzymatically converted in the skin into the active form, retinoic acid. Retinyl palmitate is first converted to retinol, which is then converted to retinaldehyde before being finally converted to the biologically active retinoic acid. Because the conversion is incomplete, and these topical retinoids are easily oxidized and degraded, they are less effective than prescription retinoids.