Can I use retinol and AHA together?

What retinol and AHA do

AHAs such as glycolic acid loosen the connections between surface skin cells, helping old cells shed. Retinol is a vitamin A based retinoid used to improve uneven skin tone, pigmentation and texture. Some over the counter retinol labels do not have to list the percentage, which makes the bottle a poor measuring instrument even when its front looks very certain.13

Retinol and AHA can share a week without being invited to the same night; that is less glamorous than a two bottle layering routine, and more useful.1

How to use them together

Introduce one active at a time so any irritation is easier to trace to its source, rather than turning troubleshooting into a group project with no useful minutes.2

1. 1Test a little glycolic acid on one area of skin first and see how your skin reacts.
2. 2Use glycolic acid at night once or twice a week to begin, then increase frequency only if your skin tolerates it.
3. 3Use retinol on nights without AHA. Retinoid guidance suggests starting every other night and building gradually, but use it less often if that schedule would overlap with AHA nights.
4. 4Keep glycolic acid and retinol on separate nights instead of applying both in the same routine.
5. 5Use broad spectrum SPF 30 or higher every day; apply it during daylight and reapply every two hours.

What results and irritation should you expect?

Glycolic acid exfoliates dead skin cells, which can leave skin looking brighter and smoother. Over the counter glycolic products can take several months of consistent use before brightness or pigmentation changes become noticeable; a faster result is not promised by the word acid.2

Too much exfoliation can irritate skin, and glycolic acid overuse can cause dryness and increased sun sensitivity. Retinoids can also irritate skin and increase sensitivity to the sun. If redness, dryness or irritation appears, stop increasing the frequency and ask a dermatologist how to adjust; irritation from a retinoid does not by itself prove an allergy.234

Use extra caution with glycolic acid if you have sensitive or dry skin, rosacea, eczema or an active skin infection. Retinoids are probably not a good choice for people with skin allergies or dryness. If your skin is already very red or inflamed, ask a dermatologist before trying a retinoid.23

Avoid retinol and other retinoids during pregnancy. Low concentration glycolic acid is generally considered safe in pregnancy, but check with a healthcare provider before using it; check with them before using glycolic acid while breastfeeding too.23

Prescription adapalene is different from cosmetic retinol. The UK NHS leaflet for adapalene cream and gel advises avoiding peeling agents such as glycolic acid during treatment because they can add drying or irritation; follow the instructions for the exact prescription product you use.5

How to alternate retinol and exfoliating acids

Treat the products as separate slots in your week: use glycolic acid on one night and retinol on another. Start glycolic acid once or twice weekly, and introduce the second product only after the first is going well on its own. Increase the frequency of one product at a time, keeping both on separate nights.12