First of all, why would you even want to use retinol? Well, in short, it's one of the most effective ingredients at clearing up acne, reducing sun spots and is currently the only topical ingredient that's FDA approved to treat lines and wrinkles. If you need to brush up on how exactly retinol does all of this neat stuff, you may want to check this out first.
The important thing to know if you decide you may be interested in a course of treatment that includes retinol: over-the-counter retinol products are not the same as prescriptions like tretinoin.
Over-the-counter products that contain retinol, regardless of whether it’s listed as simply retinol or as retinyl palmitate (aka vitamin A palmitate) are about 20 times less potent than the active chemical in prescription tretinoin: all-trans retinoic acid. That’s because the over-the-counter ingredients, in order to function as the prescription strength does, must first be converted to retinaldehyde, and converted once again to all-trans retinoic acid in order to be effective. Whether or not this conversion will even take place depends on the stability of the product; retinol is light sensitive and breaks down easily if not formulated, packaged and stored appropriately.
This doesn’t mean that some over-the-counter options aren’t viable, it’s just really difficult to know if you’re getting one that is or isn’t. Manufacturers rarely reveal the percentage of retinol in their formulation, but if you can find one that does, keep in mind you'll likely need one with at least .5% or more to equal the level of potency of a .025% prescription cream (the lowest concentration that I'm aware of). Even then, the chemical conversion that needs to take place with over-the-counter options take time to occur in the skin, so it could take twice as long to see results. The good news is that over-the-counter retinol and retinyl palmitate options are sometimes less irritating that prescription strength treatments, though I can tell you as a person who has (according to my dermatologist) "very, very, very, very sensitive skin" (4 very's, I counted!) I have been able to use prescription retinol with fairly minimal irritation- in fact, I've had worse reactions to some alpha-hydroxy acid treatments than I have to my retinol!
Another thing to throw on the scale is price. As I mentioned before, there are over-the-counter retinol treatments available at every price point imaginable. High praise has gone to drugstore treatments by ROC and Neutrogena, both retailing for less than $15 an ounce, while prestige brands like Sisley and Cle de Peau have treatments that literally cost more per ounce than a month's rent! By comparison, my tube of .025% tretinoin cream cost me about $90 at my grocery store pharmacy. I chose the generic version, which my derm assured me was identical to the much more expensive name brand Renova. The tube it came in is 45g, or 1.59 oz. That means by weight, I paid $56.60 an ounce for prescription tretinoin. Doing the math I realized, it’s actually cheaper than many over-the-counter options!
Retinol is a great product, and it can make all the difference to some users. Of course, not everything works for everybody, and it's important to find the right balance of products for your skin type and concerns. The things I discovered in my research made me decide to take the plunge and get a prescription. After years of buying pricey over-the-counter treatments, the piece of mind that I got from knowing that what I was buying was actually going to be as effective as possible made it a simple decision.