Published on: November 4, 2026
November 7 is National Retinol Day, and it’s a good excuse to talk about the single most studied ingredient in anti-aging skincare. If I could recommend only one product to most adults who want healthier, younger-acting skin, aside from sunscreen, it would be a retinoid. Retinoids have more than fifty years of research behind them. They treat acne, fade dark spots, smooth texture, and are among the very few topical ingredients shown to build new collagen in skin.
They are also the ingredient I see used incorrectly more than any other. Patients come in confused about the difference between retinol and tretinoin, unsure which strength they should be on, using three products that all contain the same thing, or convinced they “can’t tolerate retinoids” after one rough week. Most of that confusion is fixable. Here’s what I tell patients in my office.
“Retinoid” is the umbrella term for the whole family of vitamin A ingredients. Retinol is one member of that family. Tretinoin is another. People use the words interchangeably, and that’s where much of the confusion starts.
The form your skin actually uses is retinoic acid. Tretinoin is retinoic acid, applied directly to the skin, and it’s available by prescription only. The over-the-counter forms, including retinol, retinaldehyde (often called retinal), and retinyl esters such as retinyl palmitate, all have to be converted by your skin into retinoic acid before they do anything. Each conversion step loses some strength along the way.
There’s also adapalene, sold over the counter as Differin gel. It’s a synthetic retinoid originally developed for acne, and it became available without a prescription in 2016. It works well for breakouts and is a reasonable starting point for acne-prone skin, though tretinoin has a much deeper body of research for aging skin.
Retinoic acid acts on receptors inside your skin cells and changes which genes those cells switch on. In practical terms, that does several things at once. It speeds up the rate at which surface skin cells turn over, so dull, rough skin is replaced faster. It keeps pores from clogging, which is why retinoids have been a mainstay of acne treatment since the early 1970s. It breaks up and evens out pigment, so sun spots and dark marks fade. And it signals the deeper layer of skin to make more collagen while slowing the breakdown of the collagen you already have.
That last effect is what made tretinoin famous. In the 1980s, researchers studying tretinoin for acne noticed that their patients’ skin was also looking smoother and younger. Follow-up studies, including a well-known trial published in JAMA in 1988, confirmed that tretinoin improves fine wrinkles, roughness, and sun damage. In 1995, the FDA approved a tretinoin cream specifically for sun-damaged skin. Very few skincare ingredients have that kind of track record.
Because over-the-counter retinoids have to be converted before they work, the percentage on the label doesn’t tell you much on its own. A 1% retinol and a 0.025% tretinoin are not comparable numbers. Tretinoin is far more potent per percentage point, because it skips the conversion steps entirely.
Here is the family, roughly from gentlest to strongest:
Retinyl esters (retinyl palmitate, retinyl acetate) are the mildest. They need several conversion steps, and by the time they reach retinoic acid, very little activity is left. They’re often included in moisturizers more for the label than for the result.
Retinol is the most common over-the-counter retinoid, usually sold between 0.1% and 1%. It needs two conversion steps. Studies show it produces many of the same changes in skin as tretinoin, at a lower intensity and with less irritation.
Retinaldehyde (retinal) is one step away from retinoic acid, so it works faster and somewhat stronger than retinol at a similar strength, and it tends to be well tolerated.
Tretinoin is the prescription form, typically available from 0.01% to 0.1% in creams, gels, and microsphere formulas. It’s the most studied retinoid, and by far the most likely to cause irritation.
One more thing about over-the-counter products: retinol breaks down when it’s exposed to light and air. Look for opaque, airtight packaging such as a pump or tube, not a clear jar you open every night.
The best retinoid is the one you will actually use consistently. A strong product that sits in a drawer because it burned does nothing for you, while a well-tolerated one used nightly for years makes a visible difference.
For most people, that means a well-formulated over-the-counter retinol, not prescription tretinoin. At Glow Medispa, the retinol we recommend is SkinMedica. SkinMedica is one of the few skincare companies that has done studies to document how potent its retinols are, rather than leaving you to guess from the percentage on the label. Its 0.5% retinol is comparable in strength to a 0.05% prescription tretinoin, and it is much better tolerated. It also comes in lower and higher strengths, so we can start gently and step up. For these reasons, I recommend SkinMedica retinol to most of my patients and very rarely prescribe tretinoin for anti-aging.
Why is retinol so much easier on the skin? It comes down to where the ingredient does its work. Tretinoin is already retinoic acid, so when you apply it, it bathes both the outside and the inside of your skin cells, and that is a big part of why it’s so irritating. Retinol is taken up into the cell first and converted to retinoic acid there, where it’s needed. The result is a similar benefit with far less redness, peeling, and stinging.
Prescription tretinoin still has an important place. At Glow Medispa, we have several prescription topicals containing tretinoin that are formulated for specific problems, such as acne and melasma. For those conditions, a prescription is often the right tool, and we’ll decide together whether it makes sense for you.
Most people who tell me they “can’t use retinoids” started too fast. The adjustment period is predictable, and you can make it much easier with a slow start.
Use it at night. Light breaks down many retinoids, and evening application fits naturally into most routines.
Apply to clean, fully dry skin. Damp skin absorbs more and increases irritation, so wait several minutes after washing.
Use a pea-sized amount for your entire face. More product means more irritation, not faster results. Dot it on the forehead, cheeks, and chin, then spread it thinly, keeping a little distance from the corners of your nose, mouth, and eyes, where skin is thinnest.
Start low and go slow. For someone who has never used a retinol, we start with SkinMedica’s 0.25% retinol and build up in stages, using moisturizer as a buffer at first.
Phase one: buffered. Apply your moisturizer first, then the retinol on top of it. The moisturizer acts as a buffer and softens the retinol’s effect. Use it every third night, with just moisturizer on the other nights. After a week or two with no irritation, move to every other night for a week or two. If your skin is still comfortable, move to every night, still applying the retinol over your moisturizer.
Phase two: unbuffered. From here on, you use the retinol every night. What changes is the order. On an unbuffered night, the retinol goes on first, directly on clean skin, and the moisturizer goes on top. Start with one unbuffered night out of every three: two nights buffered, then one night unbuffered. After a week or two with no issues, alternate: one night buffered, the next night unbuffered. Once your skin is comfortable with that, apply it unbuffered every night. That’s the goal: retinol every night, straight on the skin, with moisturizer on top.
If your skin gets irritated at any step, go back to the previous step until it settles, then move forward again. The whole process usually takes six to twelve weeks, and that’s fine. Each step gives your skin a small, manageable increase, which is exactly how it learns to tolerate retinol.
Simplify everything else. While your skin adjusts, hold off on scrubs, exfoliating acids, and other strong actives on the same night. Vitamin C and other anti-aging serums in the morning pair well with a retinoid at night.
Wear sunscreen every single day. Using a retinoid without daily sunscreen undoes much of the benefit.
In the first two to six weeks, it’s common to have some dryness, flaking, tightness, and mild redness. This is sometimes called retinization, and it settles as your skin adapts. People with acne may also notice a temporary flare as clogged pores clear out faster. If you push through gently, by cutting back on frequency rather than quitting, most people come out the other side with calmer, clearer skin.
What isn’t normal is burning that persists, raw or weeping skin, swelling, or a rash that keeps spreading. Stop the product and let us take a look.
Patience matters. Acne and texture often start improving within six to twelve weeks. Fading of dark spots takes a few months. Collagen remodeling, and the softening of fine lines that comes with it, takes six months to a year of steady use. Retinoids are a long game, and they keep working for as long as you keep using them.
You may have heard of retinol stacking. The idea is to rotate your retinols, alternating between different products or strengths from night to night, so you can keep using them without the redness, peeling, and irritation.
It sounds clever, but it solves a problem that shouldn’t exist. If you need to rotate your retinols to keep your skin from reacting, that tells me one of two things, and often both: you started with a dose that’s too strong for your skin, or you haven’t given your skin the time it needs to adjust.
Skin needs time to adjust to being fully retinized. With slow, steady exposure, your skin gets used to retinol, and the dryness and irritation fade. That’s the purpose of the stepped schedule above. Once you’re retinized, you can use your retinol every night without a workaround. (Most people can get there without a ton of symptoms or irritation. Some people with a tendency towards redness and rosacea can't tolerate a retinol, but most people can.)
Stacking keeps your skin from ever getting there. If you’re constantly switching products and strengths, your skin never settles into a consistent dose, and you can end up needing to stack forever, with more products to buy and a more complicated routine than you need. If your retinol is irritating your skin, the fix is to drop back to a lower strength or a buffered schedule and rebuild slowly, not to add more products to the rotation.
Retinoids are not recommended during pregnancy, and most physicians advise stopping them if you’re trying to conceive. If you’re breastfeeding, talk with your doctor before starting. A few alternatives, such as azelaic acid, can cover some of the same ground in the meantime.
If you have rosacea, eczema, or very reactive skin, a retinoid may still be possible, but the product, strength, and schedule need more care. If you have a deeper skin tone, retinoids are an excellent tool for dark spots and uneven tone, but irritation itself can trigger new dark patches, so a slow start matters even more.
If you’re taking isotretinoin (Accutane), skip topical retinoids, including retinol, for the duration of your course. Your skin is already dry and fragile, and adding a retinoid mostly adds irritation. Once your course is finished, your prescriber can advise you on when to start one.
A retinoid is the daily foundation. In-office treatments build on it. Retinoids help skin respond well to treatments like chemical peels, laser resurfacing, BBL photorejuvenation, and microneedling, and they help maintain your results afterward.
The timing matters. Because retinoids make skin more sensitive, we typically ask patients to pause them for several days before treatments such as peels, laser, dermaplaning, and microneedling, and to wait until the skin has healed before restarting. The exact window depends on the treatment and your skin, so we’ll give you specific instructions when you book. Please tell us about every retinoid you use, including over-the-counter ones and the eye cream you might not think counts.
Retinoids earned their reputation. They have decades of research behind them, they work on acne, pigment, texture, and collagen all at once, and they’re affordable compared to almost anything else that delivers similar results. The difference between retinoids that transform your skin and retinoids that irritate it usually comes down to choosing the right form and strength, starting slowly, and sticking with it.
If you’d like help sorting out your routine, choosing the right retinol strength, finding out whether a prescription makes sense for acne or melasma, or planning how a retinoid fits alongside in-office treatments, book a consultation at Glow Medispa in West Seattle or Kirkland. We’ll build a plan that fits your skin.
Dr. Kate Dee is the founder of Glow Medispa in West Seattle and Kirkland. She is a Yale-trained physician with a deep interest in skin health, hormones, and medical aesthetics.
Related reading: Your Skin Doesn’t Need One Treatment. It Needs a Plan.
