# A-05 — Azelaic Acid

Does several useful things at once for skin that is inflamed and pigmenting simultaneously, which describes a great many people over thirty. The cheapest prescription in this register.

- **Canonical:** https://www.30plusskin.care/actives/azelaic-acid
- **Site:** 30+/SKIN — Skincare, published as a spec sheet.
- **Issue:** ISSUE NO. 12 / REV. 2026.08
- **Standing terms:** INDEPENDENT · AFFILIATE-FUNDED · NOT MEDICAL ADVICE

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## Datasheet

- **INN / INCI:** Azelaic acid
- **Also known as:** Nonanedioic acid
- **Family:** Dicarboxylic acid
- **Molecular weight:** 188.22 g/mol
- **Layer reached:** EPIDERMIS
- **Prescription only:** yes
- **Evidence grade:** A
- **Controlled trials on file:** 2
- **Strength range recorded:** 4%–20%
- **Best-evidenced strength:** 15%
- **Irritation (0–10):** 6
- **Onset:** 12 WK
- **Stability:** STABLE

## Mechanism

Normalises keratinisation, reduces reactive oxygen species and interferes with cathelicidin processing — the pathway now understood to be central to rosacea. Also a competitive tyrosinase inhibitor, which is why it turns up in pigment formulas.

## Measured endpoints

| Endpoint | Effect vs comparator | Window | Record |
| --- | --- | --- | --- |
| IGA success, rosacea trial 1 | +8.7% | 12 WK | REF-07 — Finacea Foam — trial 1, papulopustular rosacea (Multicentre randomised, vehicle-controlled; mean subject age 50.6, range 19–92, n=961, grade A) |
| IGA success, rosacea trial 2 | +10.9% | 12 WK | REF-08 — Finacea Foam — trial 2, papulopustular rosacea (Multicentre randomised, vehicle-controlled; mean subject age 50.6, range 19–92, n=401, grade A) |

## Layering

- **Do not layer with:** Broken or abraded skin, Eyes and mucous membranes
- **Pairs with:** Metronidazole, Ivermectin, Niacinamide

## Notes

- 15% is approved for rosacea and 20% for acne. Every other figure in this register — 17%, 14%, 10%, 6%, 4% — is an assumption about a dose-response curve nobody has drawn.
- The rosacea trials were the first programme in this register whose subjects had a mean age above thirty: 50.6, range 19 to 92. Two others have since joined it, and all three are diseases of midlife or later.
- Hypopigmentation has been reported. The label instructs monitoring in patients with dark complexions and concedes the drug has not been well studied in them.
- It stings. A foam vehicle is an attempt to soften that and nobody has published a comparison against the gel.

## Products in the register containing it

| No. | Product | Stance | Score | Document |
| --- | --- | --- | --- | --- |
| R-42 | LEO Pharma Finacea Foam | RECOMMENDED | 81/100 | /reviews/finacea-foam-azelaic-acid |
| R-33 | Alloy Rosacea Face Cream Rx | CONDITIONAL | 70/100 | /reviews/alloy-rosacea-face-cream |
| R-43 | Nurx Prescription Skincare | CONDITIONAL | 74/100 | /reviews/nurx-prescription-skincare |
| R-45 | Skin + Me The Daily Doser | CONDITIONAL | 70/100 | /reviews/skin-and-me-daily-doser |
| R-24 | Dermatica Rosacea Treatment | CONDITIONAL | 71/100 | /reviews/dermatica-rosacea |

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## Elsewhere in the register

- [Review register](/reviews)
- [Active monographs](/actives)
- [Brand register](/brands)
- [Evidence register](/evidence)
- [The ledger](/ledger)
- [How we test](/how-we-test)
- [Agent guide](/llms.txt)
- [Sitemap](/sitemap.xml)

_EVERY FIGURE RESOLVES TO A RECORD. NO NUMBER ON THIS SITE IS AUTHORED BY US._