What is the difference?
| What matters | Azelaic acid | Salicylic acid |
|---|---|---|
| Main action | Reduces inflammation and helps prevent blocked follicles. | Exfoliates and unplugs blocked follicles. |
| Best reason to choose it | Acne with inflamed bumps, or acne that leaves brown marks. | Acne where clogged pores are the main concern. |
| Other uses | Treats rosacea with inflamed bumps. | Also used in acne washes for small inflamed bumps and pimples containing pus. |
| Available forms | Cream, lotion and gel. | Cleanser and lotion. |
| Strength and texture | Clinical preparations include 15% gel and 20% cream or lotion. | Directions depend on whether the product is a cleanser or lotion. |
Both are recommended topical acne options, so the word 'acid' is not doing the choosing for you. There is no clear evidence that one beats the other for acne in general. A review of 49 trials found low quality evidence for most comparisons; azelaic acid probably produced a worse response than benzoyl peroxide and little or no difference compared with tretinoin. Choose by the problem you want to treat, rather than assuming either ingredient is the strongest acne treatment available.56
Does redness change the choice?
Redness around a pimple can be part of inflammation, alongside swelling and pain. That makes azelaic acid's inflammation reducing action useful. Brown marks left after acne are a separate concern: azelaic acid can help fade those too. Salicylic acid is not only for blackheads, though. Acne washes containing it are also used for small inflamed bumps and pimples containing pus.134
How should you use them?
Creams, gels, lotions and cleansers are ways to deliver topical acne treatment, not a podium for the most impressive sounding bottle. Choose a routine that follows the directions for the actual product, rather than treating every acid product as interchangeable.1
- 1Cleanse gently. Wash your skin twice a day and remove makeup at the end of the day.
- 2For azelaic acid cream, apply to the acne affected area initially once daily after cleansing. If tolerated, build up to twice daily.
- 3For a salicylic acid acne wash, twice daily use is an option for small inflamed bumps. Follow that product's directions; do not transfer wash instructions to a lotion.
- 4Avoid scrubbing and excessive exfoliation. Both can irritate skin, and scrubbing can make acne worse.
How long should you wait?
Most acne treatments take at least four to six weeks to make a noticeable difference. Azelaic acid often starts improving acne after about four weeks, with maximum improvement after six months of continuous use. Rosacea can take up to 12 weeks to start improving. If pimples containing pus have not improved after six to eight weeks of treatment, see a dermatologist rather than repeatedly switching products.124
Who should be careful?
Azelaic acid can irritate very sensitive skin or eczema. Avoid it if you are allergic to azelaic acid or a component of the formula. Stop using the cream and seek medical advice for severe redness, scaling, itching or burning. Seek medical advice if asthma worsens during use. Skin lightening can occur and is more apparent in darker skin tones.2
When is choosing an acid not enough?
Get medical help for deep painful lumps, scarring, widespread acne or acne that is not improving with treatment. Hot, swollen and red skin needs assessment for infection; redness can be harder to see on brown and black skin. Acne affecting your mental health is also a reason to seek help. Moderate or severe acne can need prescription treatment alongside products applied to the skin.17
Where this answer comes from
- 1How To Get Rid Of Acnedermnetnz.org
- 2Azelaic acid: Uses, Application and Moredermnetnz.org
- 3Acne: Types, Causes, Treatment & Preventionmy.clevelandclinic.org
- 4How to treat different types of acneaad.org
- 5Acne clinical guidelineaad.org
- 6Topical azelaic acid, salicylic acid, nicotinamide, sulphur, zinc and fruit acid (alpha‐hydroxy acid) for acnemedicinesresources.nhs.uk
- 7Acnenhs.uk
