Salicylic acid also has anti-inflammatory properties, which is why it’s often found in prescription creams for psoriasis as well as many over-the-counter creams.

3. Salicylic acid for exfoliating keratosis pilaris bumps

Keratosis pilaris, commonly referred to as ‘chicken skin’, is characterised by small, hard bumps on the upper arms, thighs and cheeks. “The bumps are caused by a buildup of keratin, a key protein in skin, hair and nails,” says Dr Thomson.

“In keratosis pilaris, the keratin forms a scaly plug that blocks the opening of the hair follicle, leading to patches of rough, bumpy skin,” he continues. “Salicylic acid can help improve the appearance of keratosis pilaris over time by softening and exfoliating these keratinous skin bumps.”

What is the difference between salicylic acid and glycolic acid?

Both salicylic and glycolic acids are classed as hydroxy acids and chemical exfoliants. But that’s where the similarities end.

“Glycolic acid is an alpha-hydroxy acid (AHA), whereas salicylic acid is a beta-hydroxy acid (BHA) with bigger molecules as it works superficially on the skin’s surface,” says GP and aesthetician Dr Ahmed El Muntasar. Salicylic acid is small enough to enter and de-clog pores, but “glycolic acid has even smaller molecules, so it goes deeper and stimulates collagen production,” Dr El Muntasar explains.

Can you use salicylic acid every day?

Most people can use salicylic acid every day but it depends on the product and your individual skin tolerance.

Skin specialist and A-list facialist, Shane Cooper, says: “If it’s a small amount of salicylic acid in a cleanser, for example, it is generally OK for everyday use [for most skin types]. But if it is in any other skincare product, I would recommend using it in moderation as salicylic acid can sometimes irritate the skin.”

In practical terms, this means using a salicylic acid serum once a week if you have sensitive skin; otherwise, start with three times a week and work up from there, adds Shane.

Can salicylic acid damage your skin?

With a few exceptions, salicylic acid is generally tolerated by most skin types. But there is one key side effect to be aware of. “Salicylic acid can be drying,” says Debbie, “which may lead to flaking and then irritation.” So, use it in moderation (as suggested above) and rehydrate skin by ensuring you’re topping up the hydration levels with a good barrier-building moisturiser.

It’s also important to wear sunscreen while using salicylic acid-based skincare. “Salicylic acid, like retinoids, can increase your skin’s sensitivity to the sun and lead to quicker sunburns and skin damage,” Dr Thomson notes. “Use a sunscreen with an SPF of at least 30, even on cloudy days, and limit sun exposure while using products with salicylic acid,” he says.

Who should avoid salicylic acid?

While salicylic acid is excellent for those with oily and acne-prone skin, not all skin types can tolerate this ingredient. “You shouldn’t use salicylic acid if you are allergic to aspirin,” warns Shane. “Those with super sensitive skin or rosacea may also want to avoid it, as salicylic acid can cause irritation.”

Overall, salicylic acid is safe to use during pregnancy, says Shane. “But be aware that skin can change and become more sensitive as a result of hormone changes,” he adds.

What are the best salicylic acid products to fight acne?

To work, salicylic acid needs to be in a high enough percentage – between 0.5%-2% –rather than be buried at the bottom of an ingredients list.