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The two are often believed to be interchangeable, but the main difference is that retinol is eventually converted into retinoic acid. Retinol is a natural form of vitamin A, while Retin-A is derived from retinoic acid, a synthetic derivative of vitamin A, and considered pharmaceutical.
The two forms of retinoids that I use most often are prescription retinoic acid (called tretinoin, which is found in Retin-A and Renova) and retinol. Retinol products are non-prescription, so you donât need a trip to the doctor to add retinol to your anti-aging skin care routine.