Can you use AHA and BHA together?

Yes, you can use an AHA and a BHA together, with spacing. AHA means alpha hydroxy acid, and glycolic acid is the best-known one. BHA means beta hydroxy acid, which in skincare means salicylic acid. Studies and clinics combine the two, and a 2026 review says the results for the pair are consistently positive. The American Academy of Dermatology (AAD) adds the limit: both are exfoliants, and over-exfoliating leaves skin red and irritated. So the answer is yes, used less often than either one alone, with sunscreen every morning. It is part of Skinli's guide to which skincare ingredients you can mix.

The short answer

Question	What the sources say
Verdict	Yes, with spacing
Reason	Studies combine glycolic and salicylic acid with good results, but the AAD warns against over-exfoliating
How	Use them on different days or in one product, start a few times a week, and use sunscreen daily
Main sources	AAD exfoliation page, a 2026 review, FDA pages on AHAs and BHAs
Evidence strength	Small studies, mostly of clinic peels and multi-ingredient products

What AHAs and BHAs do

The AAD says there are two ways to exfoliate at home. Mechanical exfoliation uses a brush, pad, sponge or scrub. Chemical exfoliation "uses chemicals, such as alpha and beta hydroxy acids, to dissolve dead skin cells."

Salicylic acid is the BHA used for acne. MedlinePlus says it treats acne by reducing swelling and redness and unplugging blocked pores. The 2024 AAD acne guideline makes a conditional recommendation for it, and says it is sold over the counter at 0.5 to 2 percent.

Glycolic acid is the most common AHA. The same guideline says the evidence is insufficient to make a recommendation on topical glycolic acid for acne. Glycolic acid is on the AAD's list of store-bought ingredients that can fade dark spots, and the 2025 survey of dermatologists published in the Journal of the American Academy of Dermatology agreed on it for acne and dark spots.

A 2026 review in Skin Health and Disease describes the difference this way: AHAs mainly improve surface texture and pigmentation, while BHAs such as salicylic acid reach into pores, target oily skin and reduce inflammation.

What the studies show about the pair

Most of the evidence on the two together comes from clinics and from products that mix several ingredients.

• A combined clinic peel. A 2018 split-face trial, where each person got one treatment on each half of the face, tested a peel of 50 percent glycolic acid with 0.5 percent salicylic acid in 20 people with acne. It reduced acne as much as a standard peel called Jessner's solution, and the glycolic side had fewer side effects.
• The two peels head to head. A 2008 split-face trial in 20 people compared a 30 percent glycolic acid peel with a 30 percent salicylic acid peel, given every 2 weeks for six sessions. Both worked equally well. The salicylic acid side kept its effect longer and had fewer side effects.
• A home serum. The 2026 review describes a study of 66 people with acne who used a serum of salicylic and glycolic acid for 2 weeks, with most reporting improvement.
• With a retinoid. A 2019 study of 25 people mixed a product holding glycolic acid, salicylic acid and other ingredients with 0.1 percent adapalene, and found "no hindrance" compared with adapalene alone over 28 days.

The same 2026 review is frank about the limits. It says studies "consistently report positive outcomes for SA and GA, particularly in combination treatment", and in the same sentence that most have small samples, short durations and open-label designs, meaning the people knew what they were using.

Clinic peels are far stronger than home products, and in these studies they were given in a clinic, 2 weeks apart. The results above show the two acids can work side by side. They do not show that daily use of two strong home products is safe.

Why spacing matters

Two exfoliants add up. The AAD's exfoliation advice is clear on three points:

1. Do not over-exfoliate. "Generally, the more aggressive the exfoliation, the less often it needs to be done. Be careful not to over-exfoliate, as this could lead to skin that is red and irritated."
2. Match the method to your skin. The AAD says people with dry, sensitive or acne-prone skin may prefer a mild chemical exfoliator, and people with oily, thicker skin may use stronger ones.
3. Take care with darker skin. The AAD says to avoid strong chemical or mechanical exfoliation if you have a darker skin tone or get dark spots after acne, because more aggressive exfoliation can lead to more dark spots.

How to use both

No source read for this guide sets a schedule for the pair, so this plan follows the general advice above.

• Pick one product with both, or split the days. A single product that holds both removes the question of order. With two separate products, use them on different days.
• Start with a few days a week. Increase only if your skin stays comfortable. MedlinePlus says that if skin becomes dry or irritated while using salicylic acid, apply the product less often.
• Moisturize afterwards. The AAD says exfoliating can dry the skin and to apply moisturizer right after.
• Wear sunscreen every morning. The FDA says AHAs may increase sensitivity to the sun and the chance of sunburn, and advises sunscreen while using them and for a week afterwards. It says salicylic acid products should contain a sunscreen or tell users to use other sun protection.
• Test first. The AAD suggests trying a new product on a small patch twice a day for 7 to 10 days. It also says glycolic acid can irritate skin for a short time, particularly sensitive skin. See how to patch test a new skincare product.
• Do not exfoliate broken or sunburned skin. The AAD says never to exfoliate open cuts, wounds or sunburned skin.

MedlinePlus also says acne may look worse during the first few days of salicylic acid as the skin adjusts. If breakouts or irritation keep getting worse after that, stop and ask a doctor.

Reading the label

The strength of an acid product matters as much as the pairing. The FDA says the amount of exfoliation an AHA causes "depends on the type and concentration of the AHA, its pH, and other ingredients in the product." It also says some products sold as "skin peelers" hold high amounts of AHAs or other acids and are designed to remove the outer layer of skin. Those are a poor choice to pair with a second acid at home.

Salicylic acid is easier to read. Over-the-counter acne products in the US hold 0.5 to 2 percent, the range the 2024 AAD guideline gives, and the percentage is printed on the Drug Facts panel. The FDA says a product sold to treat acne counts as a drug.

If an AHA product gives no percentage on the label, treat the product as strong until your skin shows otherwise, and use it on fewer days.

Look for the sun warning too, and keep it in mind for any product that holds either acid. The FDA suggests AHA products carry a "Sunburn Alert" that tells users to use a sunscreen, wear protective clothing and limit sun exposure while using the product and for a week afterwards.

Acids with retinoids, benzoyl peroxide or niacinamide

Adding a retinoid changes the answer. The AAD says exfoliating while using retinol, a prescription retinoid or benzoyl peroxide may worsen dry skin or even cause breakouts, and an NHS hospital leaflet says to avoid peeling agents such as salicylic acid and glycolic acid while using adapalene. Skinli's plan follows the adapalene label and does not use salicylic acid at the same time. See salicylic acid with retinol and glycolic acid with retinol.

For salicylic acid with benzoyl peroxide, see Skinli's guide to salicylic acid vs benzoyl peroxide. For a gentler partner, see salicylic acid with niacinamide.

When to see a doctor

See a doctor if your acne is painful, forms deep lumps, leaves scars, changes fast, or has not improved after 12 weeks of steady care. See one too if an acid leaves burns, blisters or new dark patches. The AAD says it takes at least 6 to 8 weeks to see fewer breakouts, and Skinli's plan allows 8 to 12 weeks for skin to change.