Can you use peptides with glycolic acid (AHA)?
Generally, yes. The claim that AHAs destroy peptides such as palmitoyl pentapeptide-4 or acetyl hexapeptide-8 on your skin isn't backed by evidence, though research on layering them is scarce.
Why
Peptide bonds hold up fairly well in mild acid: in lab testing, the small GHK peptide (tested as its copper complex) stayed stable at pH 4.5 to 7.4 for two weeks at 60 °C and broke down less under acid stress than under alkaline or oxidizing stress. The 'don't mix' advice mostly comes from brand caution, and no study has shown that using an AHA lowers peptide results. The AHA itself is the part to watch for irritation and sun sensitivity.
How to use them
If your skin is comfortable, use them in the same evening routine: AHA first on clean skin, then your peptide serum or moisturizer. Wear broad-spectrum sunscreen the next morning.
Sources
- 1Physicochemical characterization of native glycyl-l-histidyl-l-lysine tripeptide for wound healing and anti-aging: a preformulation study for dermal delivery · Pharmaceutical Development and Technology, 2016
- 2Interview with Deciem (The Ordinary) Chief Scientific Officer and Dr Davin Lim · Lab Muffin Beauty Science (Michelle Wong, PhD), 2020
- 3Alpha Hydroxy Acids · U.S. Food and Drug Administration, 2022
General cosmetic information, not medical advice. Written with AI assistance from the sources above; updated October 2026.