Topical dicarboxylic acid (anti-acne / anti-rosacea) Pregnancy: There are no adequate and well-controlled studies of topically administered azelaic acid in pregnant women; animal studies do indicate the potential for effects on pregnancy and embryo-fetal development, and caution should be exercised when prescribing to pregnant women. Lactation: it is not known if azelaic acid is secreted into human milk in vivo, but passage into maternal milk may occur; less than 4% of topically applied azelaic acid is systemically absorbed and a significant change from baseline milk levels is not expected — caution should be exercised in a nursing woman and infants must not come into contact with treated skin/breast (§4.6).

Azelaic Acid 15–20%

Brand names: Finacea (15% gel — rosacea), Skinoren (20% cream — acne), Azaduo (20% gel)

Azelaic acid is a naturally occurring dicarboxylic acid used topically for mild-to-moderate acne and for the papulopustular lesions of rosacea.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Apply to the affected skin areas and rub in gently — approximately 0.5 g, equivalent to 2.5 cm (1 inch) of gel, is sufficient for the entire facial area (a 15% gel figure; see the strength caveat in the notes)

Route: Topical — cutaneous use only. Not for oral, ophthalmic or intravaginal use (US labelling). Avoid contact with the eyes, mouth and other mucous membranes; in the event of accidental contact wash with large amounts of water.

Frequency: Twice a day, in the morning and in the evening. In the event of skin irritation the amount of gel per application should be reduced, or the frequency reduced to once a day until the irritation ceases; if required, treatment should be temporarily interrupted for a few days.

SOURCE: eMC UK SPC, productName 'Finacea 15% Gel' (https://www.medicines.org.uk/emc/product/240/smpc), §4.2, cross-checked against the US label for azelaic acid gel 15% (Glenmark Pharmaceuticals Inc., DailyMed, 2021-12-23), which states 'Apply a thin layer twice daily to affected area(s)'. STRENGTH SCOPE CAVEAT: this page is titled 'Azelaic Acid 15-20%', but the ONLY labelling in the bundle is for the 15% gel. The 20% preparation is NOT covered by any source here — its regimen and its quantity per application have not been verified and must be sourced separately. The 0.5 g / 2.5 cm quantity above is a 15% gel figure and must not be transferred to a 20% preparation. METHOD: before application the skin should be thoroughly cleaned with plain water and dried (a mild skin-cleansing agent may be used); occlusive dressings or wrappings should not be used; hands should be washed after applying. Cosmetics may be applied after the gel has dried (US labelling). DURATION: use continuously over the entire period of treatment; duration varies from person to person and with the severity of the skin disorder. Acne — a distinct improvement generally becomes apparent after 4 weeks and the gel can be used over several months for optimum results; discontinue and consider other therapeutic options if there is no improvement after 1 month or the acne is exacerbated. Rosacea — a distinct improvement generally becomes apparent after 4 weeks and the gel can be used over several months; discontinue and consider other options if there is no improvement after 2 months or the rosacea is exacerbated. (US labelling: reassess the diagnosis if no improvement is observed upon completing 12 weeks of therapy.) PAEDIATRIC: adolescents 12 to 18 years of age may be treated for acne vulgaris and no dose adjustment is required; safety and efficacy have not been established for acne vulgaris below 12 years of age, or for papulopustular rosacea below 18 years of age. The US label states that safety and effectiveness have not been established in paediatric patients. No per-kg dose exists for a topical product, hence paedDose is null. ELDERLY: no targeted studies have been performed in patients aged 65 and over. HEPATIC IMPAIRMENT: no targeted studies have been performed. EXCIPIENTS: the gel contains 1 mg benzoic acid and 120 mg propylene glycol per gram; benzoic acid may cause local irritation.

Dose adjustments

Renal

No targeted studies have been performed in patients with renal impairment (§4.2).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients (eMC §4.3). The US label states 'None' under Contraindications, but directs that the gel be avoided in patients with known hypersensitivity to any component.

Side effects

Application site burning, application site pain and application site pruritus — the most frequently observed effects (very common). US trials: burning/stinging/tingling 29%, pruritus 11%
Application site rash, paraesthesia, dryness and oedema (common); application site erythema, exfoliation, warmth, discolouration, discomfort and urticaria (uncommon). US trials: scaling/dry skin/xerosis 8%, erythema/irritation 4%
Contact dermatitis and acne (uncommon)
Skin irritation and urticaria (rare); hypopigmentation reported in isolated cases (US labelling — monitor patients with dark complexion for early signs)
Hypersensitivity, which may occur with angioedema, eye swelling, swelling of the face or dyspnoea; worsening of asthma has been reported rarely in post-marketing surveillance

Interactions

No interaction studies have been performed; the composition gives no indication of undesired interactions and no drug-specific interactions were noted during any of the controlled clinical trials (§4.5)
Other topical drugs and skin care products that could cause local irritation — soaps, alcoholic cleansers, tinctures, astringents, abrasives and peeling agents — should be avoided during treatment, particularly because of the highly sensitive facial skin in rosacea (§4.4)

Clinical monograph

How it works

It has antimicrobial activity against Cutibacterium acnes and normalises follicular keratinisation, and additionally exerts anti-inflammatory effects useful in rosacea.

Prescribing in practice

Transient local irritation, burning, stinging and itching are common on initiation, particularly in the first few weeks; advise patients to persevere and reduce application frequency if troublesome.
It is a useful option in pregnancy and breast-feeding where many other acne agents are avoided, and does not cause photosensitivity.
Avoid contact with the eyes, mouth and other mucous membranes, and apply to clean, dry skin.

Monitoring

No laboratory monitoring is required; assess treatment response and tolerability clinically over several weeks.

Counselling the patient

Apply a thin layer to the affected area and rub in gently after washing.
Some tingling or burning is normal at first and usually settles with continued use.
Allow adequate time for benefit, as improvement may take several weeks.

Evidence & guidelines

Topical azelaic acid is recommended in current dermatology guidance as a treatment option for acne and rosacea.

Reference: BAD Acne Guidelines 2021; BAD Rosacea Guidelines; NICE CG184; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways