Can I use AHA with tretinoin?

Why can the combination irritate skin?

AHA means alpha hydroxy acid. These acids exfoliate by shedding surface skin cells; glycolic acid and lactic acid are common examples. Tretinoin is a prescription retinoid that increases production of new skin cells and unclogs pores. Exfoliating while using a prescription retinoid can worsen dry skin or cause acne breakouts. The practical concern is adding irritation, not simply deciding which product goes first.123

Exfoliation is not for everyone, so a bottle does not earn a place in your routine just by being available. If your skin is already dry, red or irritated, leave out the AHA rather than trying to exfoliate away the peeling. That is general exfoliation guidance applied to a tretinoin routine.1

Does the AHA strength matter?

Yes. The amount of exfoliation depends on the acid type, concentration, pH and other ingredients, not just the percentage printed on the bottle. Strong peeling products have been associated with more serious reactions. Consumer safety criteria for glycolic and lactic acid products include concentrations of 10 percent or less, a final pH of at least 3.5, and protection against increased sun sensitivity or directions to use daily sun protection. Those criteria are not permission to add a 10 percent acid to irritated skin.3

How should I use them?

1. 1Before adding AHA, discuss the product and your current tretinoin schedule with your prescriber. Do not change your prescription schedule to make room for an exfoliant.
2. 2On tretinoin nights, wash with a mild, nonabrasive cleanser and let your skin dry as directed. Apply a thin layer with clean fingertips, avoiding the eyes, mouth and corners of the nose.
3. 3If your prescriber agrees to AHA, follow that product's application and rinsing directions. Use moisturizer after exfoliating. There is no universal AHA frequency: stronger exfoliation generally calls for less frequent use.

An AHA label gives application directions, while the promise on the front has appointed itself head of sales. Do not assume every acid toner, rinse off exfoliant and peel belongs on the same schedule.3

Who should be especially careful?

Dry or sensitive skin needs particular caution. Avoid strong exfoliation if you have darker skin or develop dark spots after irritation, because aggressive exfoliation can increase pigmentation. Never exfoliate over open cuts, wounds or sunburn. Retinoids should not be used during pregnancy; discuss pregnancy plans or breastfeeding with your prescriber.124

Use sunscreen, protective clothing and limited sun exposure while using AHA and for a week afterwards. Applying acids at night does not replace daytime protection. Tretinoin also requires protection from sunlight.23

What should I expect, and when should I stop?

Tretinoin works slowly: acne sores can improve in 2 to 3 weeks, sometimes taking more than 6 weeks. Fine wrinkle improvement can take 3 to 6 months. Do not use AHA to force faster results. Leave out exfoliation if redness or irritation develops. Tell your doctor about severe or persistent burning, peeling, swelling or blistering. Call immediately for rash, hives, itching, or pain at the treatment area.2