What it is
Azelaic acid is found in grains such as wheat, rye and barley, and is produced by Malassezia furfur, a yeast that lives on normal skin. That origin is of historical interest rather than practical relevance — the medicine is manufactured synthetically.
How it works
Normalises keratinisation
It reduces the abnormal follicular hyperkeratinisation that forms the microcomedone. Acting on the earliest lesion in acne is what gives it an anticomedonal effect rather than only an anti-inflammatory one.
Antibacterial
It is active against Cutibacterium acnes and works through a mechanism that does not select for antibiotic resistance — a meaningful advantage over topical antibiotics used alone.
Anti-inflammatory
It scavenges reactive oxygen species and reduces the release of inflammatory mediators from neutrophils. This is the property that matters most in rosacea, where the papules and pustules are inflammatory rather than comedonal.
Inhibits tyrosinase
It is a competitive inhibitor of tyrosinase, the rate-limiting enzyme in melanin synthesis, and appears to act preferentially on hyperactive melanocytes. That selectivity is why it is used for post-inflammatory hyperpigmentation without depigmenting normal skin.
What it is prescribed for here
Acne. As a single agent for mild to moderate acne, particularly where post-inflammatory hyperpigmentation is part of the complaint, where a retinoid has not been tolerated, or where the skin is already irritable. Rosacea. For the papulopustular phenotype, either as a single agent at 15% or as the micronised 10% component of the compounded erythema cream, alongside metronidazole 0.75%, niacinamide 4% and allantoin 0.5%. A doctor decides which of these, if any, applies to a given case. Nothing on this page is a recommendation to use it.What has been reported
Azelaic acid’s side-effect profile is dominated by local reactions, and by one in particular.The stinging is not an allergy and it is not a sign the medicine is too strong.
It is a characteristic effect of the molecule. Applying to completely dry skin
rather than damp skin, and starting at a reduced frequency, are the two things
that most reliably reduce it. The
application guide covers this.
Where it sits against the alternatives
Azelaic acid is generally better tolerated than a topical retinoid and less bleaching than benzoyl peroxide, but it is also slower and, for straightforward inflammatory acne, usually less potent than a retinoid–benzoyl peroxide combination. Its distinguishing advantages are the pigment effect and the tolerability, which is why it is a common first choice in darker phototypes where post-inflammatory hyperpigmentation is often more distressing than the acne itself. Unlike benzoyl peroxide, it does not bleach fabric.Who it is not suitable for
Anyone with known hypersensitivity to azelaic acid or to an excipient in the formulation. Beyond that, suitability is a judgement the reviewing doctor makes from the questionnaire — including in pregnancy and breastfeeding, where the decision belongs to the doctor and requires knowing before a prescription is issued, not after.Realistic timelines
1
Weeks 1–2
Stinging on application; possible dryness. This is the phase most people stop in, and it is the phase that passes.
2
Weeks 4–8
Inflammatory lesions typically begin to reduce. Pigment change is not usually visible yet.
3
Weeks 8–12
The usual point of fair assessment for the acne or rosacea effect.
4
Months 3–6
Post-inflammatory pigment fades on a slower clock than the lesions that caused it, and only if the area is protected from sunlight.
How Hi-Doctor handles it
The consultation is fully asynchronous: there is no video call and no telephone consultation. You answer the questionnaire, upload a photograph, and a registered doctor reviews the case and decides. If they do not issue a prescription, the consultation fee is refunded in full. The medicine itself is dispensed and paid for at a pharmacy of your choosing — the pricing page covers what the consultation fee includes.Related reading
- Acne · rosacea
- Adapalene · benzoyl peroxide · topical clindamycin
- Metronidazole · ivermectin · niacinamide
- How to apply a prescription topical
- Side effects of dermatology topicals
- Safety and eligibility
Start a consultation
Acne consultation
Answer the acne questionnaire and a registered doctor reviews it. If your
concern is rosacea instead, the
rosacea pathway is the right starting point.
Declining is a normal outcome. See what it costs and
how the review works.