If you can’t stop, won’t stop buying skin care products, you probably have a retinol and glycolic acid products sitting in your medicine cabinet. But how the heck do you choose? And can they actually be used together?

Listen up, skin care fanatics: Here’s what the science says about using retinol and glycolic acid.

Glycolic acid is an alpha hydroxy acid (AHA) that comes from sugar cane. It acts as a chemical exfoliant and helps resurface your skin by dissolving bonds between skin cells, making it easy to get rid of dead skin.

This skin refresh can help even out skin tone and treat skin discoloration (aka hyperpigmentation) and acne. Glycolic acid can also help other treatments, such as phytic acid, better penetrate your skin to fight hyperpigmentation and give you a luminous glow.

Retinol is a type of retinoid, which is an umbrella term for products derived from vitamin A. It’s not as strong as other retinoids, so you can get your hands on it without a prescription.

Retinol works by stimulating the production of collagen and a bunch of other compounds necessary for growing healthy skin. This is notably good for reducing the signs of skin aging, like fine lines and wrinkles. But this skin turnover effect is also good at unclogging pores to help treat acne.

Folks used to think using glycolic acid + retinol was a big no-no. But today most dermatologists agree that’s a bunch of hokum. The bad advice started with the false belief that AHAs like glycolic acid interfered with retinol’s ability to do its thing. (Spoiler: They don’t.)

In fact, adding glycolic acid and retinol to your skin care routine may help better treat acne and acne scarring. A 2015 study found that a retinol + glycolic acid combo was effective enough to help minimize the need for other acne scar treatments.

But because both ingredients can irritate your skin, derms don’t recommend mixing them or using glycolic acid and retinol at the same time. It’s better to alternate using glycolic acid and retinol.

If you’d rather use just one product, which is “better” depends on what you’re trying to achieve.

Reach for glycolic acid if:

  • You have more sensitive skin. It’s less drying than retinol and less likely to cause irritation.
  • You have oily skin, discoloration, or texture issues. Because it’s an exfoliant, glycolic acid can help slough off dead skin cells and clear out clogged pores due to excess oil.

Reach for retinol if:

  • You want to treat aging skin. Because retinol works by reinvigorating skin cells rather than clearing dead ones, it’ll help reduce the appearance of fine lines and wrinkles.
  • You have sun damage. Retinol can help you grow healthier skin where UV rays have wreaked havoc.
  • You have acne. Retinol’s boost for skin turnover can also help unclog those pores that cause acne.

While they’re both considered safe, there are, of course, some possible side effects when using retinol and glycolic acid.

Some side effects to be on the lookout for:

  • Sun sensitivity. It’s important to be strict with your sunscreen use when using glycolic acid or retinol, because both can increase your susceptibility to sunburn and sun damage.
  • Peeling/flaking. This is usually temporary, but it’s a good indication that you need to scale back the number of retinol/glycolic acid applications in your routine.
  • Redness. As with all other skin care products, red, raw-looking skin is a big adverse reaction (literally) red flag.
  • Itchiness. Redness often comes along with itchiness and irritation.
  • Hyperpigmentation. This is rare, but if you have a darker complexion, you may find that glycolic acid leaves off-color marks on your skin. To reduce the risk, avoid doubling up on the glycolic acid products in your routine, moisturize regularly, and avoid scrubbing/exfoliating your face directly after application.

FYI: It’s also recommended that pregnant/breastfeeding folks avoid retinol and other topical retinoids.

It can be pretty dang overwhelming choosing between products that contain glycolic acid or retinol. Start by identifying your #SkinCareGoals, and then choose your product accordingly.

An obvious but key tip is to check reviews and ingredient lists. Starting with lower doses is also a good idea if you’re new to the products or plan on using both.

It’s a common misconception that using glycolic acid and retinol together cancels out their benefits. If you want to use both products, you absolutely can. Just make sure to use them at alternating times of the day or days of the week.

Using glycolic acid and retinol together can be great for treating acne. But if you want to choose one, retinol is better for addressing wrinkles and fine lines, while glycolic acid acts as an exfoliant to help even out skin texture.

As with all skin care products, introduce new products with strong active ingredients gradually. If you’re noticing adverse reactions, pump the brakes and call up your dermatologist.