Azelaic acid is one of those ingredients that keeps turning up in dermatologist routines and almost never in viral skincare videos, which is usually a good sign. It treats acne, calms rosacea and fades the dark marks left behind afterwards, and it's one of the few actives considered safe in pregnancy. That's a lot of work for something you can buy for under £10.
Here's what it actually does, how to use it without irritating your face, and which product is worth buying.
What azelaic acid actually is
Azelaic acid is a dicarboxylic acid your skin already knows. It's produced naturally by the yeast that lives on your face (Malassezia), and in skincare it's made synthetically so the dose is consistent.
On an ingredients list you'll see azelaic acid. Over the counter it's usually 10%. Prescription formulas in the UK go higher: Finacea is a 15% gel, Skinoren a 20% cream. The jump from 10% to 15% is meaningful, which is why the pharmacy versions still exist.
It isn't an AHA or a BHA. It doesn't exfoliate the way glycolic or salicylic acid do. Think of it as an anti-inflammatory that also happens to unclog pores and fade pigment, rather than an acid you cycle on and off.
What it does for your skin
It treats acne. Azelaic acid is antibacterial against C. acnes, mildly keratolytic (it helps unstick the dead cells that clog pores) and anti-inflammatory, so it hits the three things driving most breakouts. Prescription 15–20% gels are licensed for mild to moderate acne; 10% over-the-counter versions do a quieter version of the same job. If your acne is mostly blackheads and congestion, salicylic acid is still the more direct tool. If it's red, inflamed spots plus the marks they leave, azelaic acid is often the better single product.
It's one of the best over-the-counter options for rosacea. A 15% gel significantly reduced both the bumps and the redness of papulopustular rosacea in large controlled trials (Thiboutot et al., 2003). That's the same evidence we lean on in our facial redness guide. The 10% OTC versions are milder, but they're a sensible starting point if you don't have a prescription yet.
It fades dark marks. Azelaic acid inhibits tyrosinase, the enzyme your skin uses to make melanin, which is why it helps post-inflammatory hyperpigmentation and patchy uneven skin tone. Searches for "azelaic acid for dark spots" are asking this exact question: yes, it is one of the better over-the-counter options, especially if retinoids have been too harsh. It won't outpace hydroquinone or a prescription retinoid for stubborn melasma, but it's one of the few pigment ingredients you can keep using long-term, including through pregnancy. For the cheap 10% bottle, see The Ordinary Azelaic Acid 10%. It also pairs well with niacinamide.
It's gentler than it sounds. Tingling for a minute after application is common, especially in the first week. True irritation is less common than with retinoids or strong AHAs, which is why it's often the active people with sensitive or rosacea-prone skin can actually tolerate.
How to use azelaic acid
Where it goes: after cleansing, before moisturiser. Same slot as any treatment serum. If you're also using a hydrating serum, azelaic acid first, hydrator second. The layering order is thin-to-thick as usual.
How often: start every other night for a week, then nightly if your skin is calm. Plenty of people use it morning and night once they're used to it. It doesn't make you meaningfully more sun-sensitive the way AHAs do, but daily SPF is still non-negotiable, especially if fading pigment is the goal.
How much: a pea-sized amount for the whole face, or a thin layer over the areas you're treating. More does not work faster.
The texture warning: some 10% formulas, The Ordinary's suspension in particular, are thick and silicone-heavy. Warm a small amount between your fingers first, then press it in. If it pills under moisturiser or SPF, you're using too much, or you haven't let it settle for a minute.
As with any new active, patch test it before putting it on your whole face.
What to pair it with (and what to skip)
Works well with niacinamide. They target overlapping problems (oil, marks, redness) through different pathways, and the combination is well tolerated. Niacinamide in the morning, azelaic acid at night is the simplest split if you don't want them in the same routine.
Works well with retinoids, on alternate nights at first. Once your skin is used to both, some people use azelaic acid in the morning and a retinoid at night. Don't stack them on the same application until you know your barrier can take it.
Be careful with other acids. You can use azelaic acid with salicylic or glycolic acid, but you usually shouldn't, at least not at the start. Pick one exfoliant. Azelaic acid plus a strong AHA is a fast way to a damaged barrier.
Vitamin C is fine in the morning if azelaic acid lives at night. Using both at once is more likely to tingle than to help.
Which product should you buy?
Start here: The Ordinary Azelaic Acid Suspension 10% (around £7–£10). Fragrance-free, widely available in the UK, and the price makes it the obvious first bottle. The texture is the trade-off: it's a thick, opaque cream rather than a serum, and it can pill. If that bothers you, The Inkey List's 10% azelaic acid serum is a thinner alternative at a similar price.
If you want a more elegant 10%: Paula's Choice 10% Azelaic Acid Booster mixes more nicely under other products, at roughly four times the price. Worth it if the Ordinary texture has already annoyed you; not worth it as a first try.
If 10% isn't moving the needle: talk to a GP or dermatologist about Finacea (15% gel) or Skinoren (20% cream). Both are licensed in the UK for acne and rosacea. That's the strength the clinical trials actually used, and it's the step that makes the difference for a lot of people.
Prescription options exist because 10% is a useful, not miraculous, concentration. Give an OTC bottle eight weeks before deciding it "doesn't work".
How long until you see results?
Acne and redness usually start settling in four to eight weeks. Pigmentation is slower: eight to twelve weeks is a realistic window, and sun protection is what stops new marks forming while the old ones fade. If nothing has changed at twelve weeks on 10%, that's when the prescription conversation is worth having, not sooner.
Who should use it, and who can skip it
Use it if: you have mild to moderate acne, rosacea-type redness, or dark marks from old breakouts, especially if retinoids or acids have been too harsh. Also if you're pregnant or trying to conceive and need something evidence-based that isn't a retinoid.
Skip it, or see a doctor first, if: your acne is cystic or scarring, your redness is getting worse rather than better, or your skin is currently raw from over-exfoliation. Fix the barrier first; add azelaic acid after it feels normal.
Azelaic acid is not a substitute for a dermatologist. Persistent rosacea, scarring acne and suspected melasma deserve a proper diagnosis.
The verdict
Azelaic acid is one of the most useful under-hyped ingredients in skincare. It won't give you a dramatic before-and-after in a fortnight, and the cheap 10% formulas are a bit annoying to apply. What it will do, with boring consistency, is calm inflamed acne, take the heat out of rosacea, and slowly fade the marks those two leave behind, without the irritation tax most actives charge.
If you only add one treatment product this year and your problems are redness, spots or leftover marks, this is a very reasonable candidate.
References
Schulte BC, Wu W, Rosen T. Azelaic Acid: Evidence-based Update on Mechanism of Action and Clinical Application. J Drugs Dermatol. 2015;14(9):964-968. (https://pubmed.ncbi.nlm.nih.gov/26355614/)
Thiboutot D, Thieroff-Ekerdt R, Graupe K. Efficacy and safety of azelaic acid (15%) gel as a new treatment for papulopustular rosacea: results from two vehicle-controlled, randomized phase III studies. J Am Acad Dermatol. 2003;48(6):836-845. doi:10.1067/mjd.2003.308 (https://pubmed.ncbi.nlm.nih.gov/12789142/)
Kircik LH. Efficacy and safety of azelaic acid (AzA) gel 15% in the treatment of post-inflammatory hyperpigmentation and acne: a 16-week, baseline-controlled study. J Drugs Dermatol. 2011;10(6):586-590. (https://pubmed.ncbi.nlm.nih.gov/21637903/)
Gollnick HP, Graupe K, Zaumseil RP. Comparison of combined azelaic acid cream plus oral minocycline with oral isotretinoin in severe acne. Eur J Dermatol. 2001;11(6):538-544. (https://pubmed.ncbi.nlm.nih.gov/11701404/)
FAQs
What does azelaic acid do for your skin?
It reduces acne, calms rosacea redness and fades dark marks. It works as an anti-inflammatory and a mild antibacterial, and it also slows melanin production, which is why leftover spots from breakouts gradually even out.
Can I use azelaic acid every day?
Yes, once your skin has adjusted. Start every other night for a week, then use it nightly. Many people use it morning and night. If it stings beyond a brief tingle, scale back and moisturise more, rather than pushing through.
Is azelaic acid better than niacinamide?
They do overlapping jobs in different ways. Niacinamide is the gentler daily all-rounder for oil, barrier support and mild pigmentation. Azelaic acid is stronger against inflamed acne, rosacea and stubborn dark marks. A lot of people use both.
Is azelaic acid good for acne?
Yes, particularly red, inflamed spots and the flat brown or red marks they leave. It's less of a specialist for blackheads than salicylic acid. For persistent or cystic acne, see a GP; azelaic acid is not a stand-in for prescription treatment.
Can you use azelaic acid with retinol?
Yes. The easiest way is azelaic acid in the morning and retinol at night, or on alternate nights until your skin is used to both. Don't layer them in the same step at the start.
Is azelaic acid safe during pregnancy?
It's one of the few acne and pigment actives generally considered acceptable in pregnancy, unlike retinoids. That still isn't medical advice: check with your midwife or GP before starting anything new.