Can I use glycolic acid with salicylic acid?
It depends on whether they arrive in one product or two. A single formula that combines them is fine. Two separate leave-on acids in one routine is where skin gets over-exfoliated.
In one formulated product, yes. As two separate leave-on products in the same sitting, no. Alternate them on different nights and keep count of how many exfoliating steps your week contains.
What each one does
Glycolic acid is water soluble and works on the surface, loosening dead cells so the skin looks smoother and more even.
Salicylic acid is oil soluble. It gets into pores and clears the mix of oil and dead cells that causes blackheads and breakouts.
They reach the same skin by different routes, which is why some products use both.
One product or two
When both acids are in a single product, the formulator has chosen the strength of each so the total stays tolerable. Use it as the label directs.
Two separate leave-on products are a different matter. Each was designed to be the only acid in a routine, and stacking them doubles the exfoliation.
How to use both
Alternate nights is the simplest plan: glycolic acid one night, salicylic acid another, with nights off in between.
Another option is to use them on different areas. Salicylic acid on the oily centre of the face and glycolic acid on the cheeks suits combination skin.
Making one of them a rinse-off also works. A salicylic acid face wash with an occasional glycolic toner is gentler than two leave-ons.
Count the week
Add up every exfoliating step you use: acid toners, exfoliating washes, scrubs, peels and masks. For most skin, two or three leave-on acid applications a week in total is plenty. More than that rarely improves the result and often damages the barrier.
Sunscreen and warning signs
Glycolic acid makes skin more sensitive to the sun, so wear sunscreen daily while using it.
Stop both acids if the skin becomes tight, shiny, flaky or stings when other products go on. Use a gentle cleanser and a moisturiser until it settles, then restart with one acid.
Cham makes no glycolic acid product and no salicylic acid product. This is guidance for products you already own.
This page describes how ingredients behave together. It does not diagnose. A prescriber, a pregnancy, or a diagnosed skin condition outranks anything written here.
Related questions
Can I use a salicylic acid face wash with a glycolic acid toner?
Usually, yes. The face wash is rinsed off and leaves little acid behind, so the toner is the only leave-on acid. Keep the toner to a few nights a week.
Which should I choose, glycolic acid or salicylic acid?
Salicylic acid suits oily skin, blackheads and clogged pores. Glycolic acid suits dullness, rough texture and uneven tone. Plenty of people need only one.
Can I use both every day?
Not as separate leave-on products. Daily use of two exfoliating acids is more than most skin can take.