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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.
Retin-A, sold under the generic name tretinoin, is a form of vitamin A that's applied to the skin to promote skin renewal. The medication is prescribed to treat acne, and to make wrinkles and fine lines smoother and less noticeable.Retin-A is also given to people that have hyperpigmentation due to aging skin.ontact your doctor if you have severe skin irritation or if your acne doesn't improve in eight to 12 weeks. While on Retin-A, it's important to avoid sunlight as well as sunlamps or tanning beds.