Salicylic acid and benzoyl peroxide help clear different types of acne and prevent breakouts. But they should not be used together on the same area of skin.

Salicylic acid and benzoyl peroxide are two of the most well-known acne-fighting ingredients. Widely available over the counter, they both help clear mild acne and prevent future breakouts.

Keep reading to learn more about the benefits and side effects associated with each ingredient and how to use them.

Both ingredients remove dead skin cells, which can clog pores and contribute to acne breakouts.

Salicylic acid

Salicylic acid works best for blackheads and whiteheads. When used regularly, it may also help prevent future comedones from forming.

Benzoyl peroxide

Benzoyl peroxide is one of the most effective acne-fighting ingredients available without a prescription. It works best on traditional red, pus-filled pimples (pustules).

In addition to removing excess oil and dead skin cells, benzoyl peroxide helps kill acne-causing bacteria beneath the skin.

Although the side effects of each ingredient vary, both products are considered safe overall. They’re also considered safe to use during pregnancy. Salicylic acid should not be used by someone allergic to aspirin.

Both ingredients may cause dryness and irritation when you first start using them. Allergic reactions are rare, but they are possible. You should seek emergency medical attention if you develop extreme swelling or have trouble breathing.

Salicylic acid

Salicylic acid dries out excess oils (sebum) in your pores. However, it could remove too much oil, making your face unusually dry.

Other possible side effects include:

  • hives
  • itching
  • peeling skin
  • stinging or tingling

Benzoyl peroxide

Benzoyl peroxide may not be safe for sensitive skin. It’s more drying than salicylic acid, so it can lead to more severe irritation.

If you have any of the following conditions, talk with a healthcare professional before use:

This ingredient may also stain your hair and clothes, so apply with caution and wash your hands thoroughly after use.

The product you choose will depend on:

  • The type of acne you have: Salicylic acid is more effective for blackheads and whiteheads. Benzoyl peroxide works well for mild pustules.
  • The severity of your breakouts: Both ingredients are intended for mild breakouts, and they can take several weeks to take full effect. Benzoyl peroxide, though, might show some benefit as an emergency spot treatment.
  • Your activity level: If you’re active during the day, sweat can transfer benzoyl peroxide to your clothing and stain it. You may consider using related products only at night or using salicylic acid instead.
  • Your overall skin health: Salicylic acid is milder and may not aggravate sensitive skin as much as benzoyl peroxide.
  • Any underlying medical conditions: Although both ingredients are available over the counter, this doesn’t mean they’re safe for everyone. Double-check with a healthcare professional if you have an underlying skin condition, or if you have kidney disease, diabetes, or liver disease.

You should never use a salicylic acid- or benzoyl peroxide-based product for every step of your skin care routine. For example, if you use a salicylic acid-based cleanser, make sure that this ingredient isn’t in your toner or moisturizer.

Using the ingredient in each step of your routine can dry out your skin and worsen your acne.

It’s also important to wear sunscreen every day and avoid tanning. Although these acne ingredients don’t cause sun sensitivity like retinoids and alpha-hydroxy acids, unprotected sun exposure can make acne worse. It may also increase your risk of skin cancer and scarring.

Salicylic acid

Topical dosages for gels, creams, washes, astringents, and other over-the-counter products usually contain concentrations between 0.5% and 7%.

Salicylic acid may be used morning and night. Because it’s so gentle, it may also be applied as a midday spot treatment.

Benzoyl peroxide

Benzoyl peroxide products are typically available in 0.5%, 5%, and 10% concentrations over the counter.

When selecting a benzoyl peroxide product, it’s best to start with a lower concentration, as it causes less drying and irritation. For example, start with 2.5% and then move to a 5% concentration if you see minimal results after 6 weeks.

You may start with a gentle wash, and then move up to a gel-based version as your skin gets accustomed to the ingredient. If you aren’t seeing results after 6 weeks, you may move up to a 10% concentration.

Benzoyl peroxide may be used up to twice per day. After cleansing and toning, apply the product in a thin layer around the entire affected area of skin. Let the product dry for a few seconds before applying your moisturizer.

If you’re new to benzoyl peroxide, start with once a day only. Gradually work your way up to morning and night applications. Some people may find every other day is best for sensitive skin.

If you use a retinoid or retinol product at night, apply benzoyl peroxide only in the mornings. This will prevent irritation and other side effects.

Your treatment plan could very well include both salicylic acid and benzoyl peroxide at the same time. However, applying both products on the same area of skin — even at different times of day — can increase your risk for excessive drying, irritation, and peeling.

A safer approach is to use both ingredients for different types of acne. For example, salicylic acid may be a good all-over method to treat and prevent breakouts, while benzoyl peroxide may be applied as a spot treatment only.

While there’s technically no cure for acne, salicylic acid and benzoyl peroxide may offer some relief and help clear up breakouts.

If you aren’t seeing results after 6 weeks, check in with a dermatologist. They may recommend stronger treatments, such as retinols or prescription retinoids.