> ## Documentation Index > Fetch the complete documentation index at: https://docs.hi-doctor.ai/llms.txt > Use this file to discover all available pages before exploring further. # Azelaic acid — how it works in acne and rosacea > Azelaic acid 15% is anticomedonal, antibacterial and anti-inflammatory, and it fades post-inflammatory pigment. How it works and what it is prescribed for. Azelaic acid is a naturally occurring saturated dicarboxylic acid used topically in acne and in rosacea. It is unusual among dermatology topicals in doing several useful things at once and being relatively gentle while doing them, which is why it is often the option considered where irritation or pigmentation is the limiting concern. ## What it is Active ingredient: **azelaic acid**. On this service it is prescribed at **15%**, on both the [acne](/library/conditions/acne) and the [rosacea](/library/conditions/rosacea) pathway. In the EU it is marketed under brand names including Skinoren and Finacea. It also appears as a micronised 10% component of the compounded rosacea erythema cream. 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 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. 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. 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. 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](/library/medicines/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. | Reported effect | Character | | -------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------- | | Burning, stinging or tingling on application | The most commonly reported effect. Typically strongest in the first one to two weeks and settles as tolerance develops | | Dryness, scaling and peeling | Common early, usually manageable with a bland moisturiser | | Erythema and itching at the application site | Common, usually mild | | Contact dermatitis | Less common; a spreading, worsening or intensely itchy reaction is a reason to stop and seek advice | | Hypopigmentation | Reported rarely, and worth watching for on darker skin tones | | Worsening of asthma | Reported rarely; relevant to mention if you have asthma | 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](/library/guides/how-to-apply-topicals) 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](/library/medicines/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 Stinging on application; possible dryness. This is the phase most people stop in, and it is the phase that passes. Inflammatory lesions typically begin to reduce. Pigment change is not usually visible yet. The usual point of fair assessment for the acne or rosacea effect. 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](/essentials/pricing) covers what the consultation fee includes. ## Related reading * [Acne](/library/conditions/acne) · [rosacea](/library/conditions/rosacea) * [Adapalene](/library/medicines/adapalene) · [benzoyl peroxide](/library/medicines/benzoyl-peroxide) · [topical clindamycin](/library/medicines/clindamycin-topical) * [Metronidazole](/library/medicines/metronidazole-topical) · [ivermectin](/library/medicines/ivermectin-topical) · [niacinamide](/library/medicines/niacinamide) * [How to apply a prescription topical](/library/guides/how-to-apply-topicals) * [Side effects of dermatology topicals](/library/guides/side-effects-dermatology) * [Safety and eligibility](/essentials/safety) ## Start a consultation Answer the acne questionnaire and a registered doctor reviews it. If your concern is rosacea instead, the [rosacea pathway](/library/conditions/rosacea) is the right starting point. Declining is a normal outcome. See [what it costs](/essentials/pricing) and [how the review works](/essentials/how-it-works). This page is reference information, not medical advice and not a prescription. Whether a medicine is appropriate for you is decided by a registered doctor after reviewing your consultation.