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How much azelaic acid do you need? 15%+

The effective azelaic acid percentage, by the vehicle-controlled trials, starts at 15%; no published dose comparison sets a ceiling.

Give it eight to twelve weeks, and possibly less: that is simply when it was measured.

how it was measured

Measured on inflammatory lesion count (papules and pustules) in papulopustular rosacea, investigator-counted; measured at the trial's end, so possibly sooner.PMID 12789172PMID 30585305PMID 38300170

See it on the timeline, beside the others →

Written by Maya Faour, founder and sole writer; not a dermatologistHow we work →Published Reviewed

Dose line for Azelaic Acid: the trials worked from 15% with no measured ceiling; ticks at 5%, 15%, 20% where the named trials worked; the highest dose tested 20% (Bjerke 1999): tolerated; catalogue labels at 10%. Linear scale.5%, Pazoki-Toroudi 201115%, Thiboutot 200320%, the highest dose tested in leave-on use on human skin (Bjerke 1999): tolerated5%10%15%20%toleratedPazoki-Toroudi 2011Thiboutot 2003highest tested, Bjerke 1999The Ordinary Azelaic Acid Suspension 10%: 10% (outside the trials’ range)0%

5%, Pazoki-Toroudi 2011.

No dose comparison found between 15 and 20%, and nothing tests 10% against vehicle; 5% gel alone cut the acne severity index by 32% where 5% with clindamycin cut it 64%, no placebo arm at that dose (Pazoki-Toroudi 2011).

The rose band is where the vehicle-controlled trials worked, open to the right because no dose comparison sets a ceiling; each tick is a concentration a named trial used, with its author and year; the last tick is the highest dose tested in leave-on use on human skin, 20% (Bjerke 1999), where the paper reports: tolerated; the bottles above the line are the products in our catalogue that declare a percentage on the name, hollow where it falls outside the trials’ range. The scale is linear.

What azelaic acid percentage is effective?

Floor 15%: two identical vehicle-controlled phase III trials of 15% gel twice daily in papulopustular rosacea, 329 and 335 patients over 12 weeks, cut inflammatory lesions 58% versus 40% and 51% versus 39% (Thiboutot 2003).

15%+

The trials, and what they used
  • 20% cream beat its vehicle in 92 acne patients over 3 months (Katsambas 1989), in 116 rosacea patients over 3 months (Bjerke 1999), in 60 acne patients over 45 days with a 61% versus 20% lesion reduction (Iraji 2007) and in facial hyperpigmentation over 24 weeks (Lowe 1998).
  • No dose comparison found between 15 and 20%, and nothing tests 10% against vehicle; 5% gel alone cut the acne severity index by 32% where 5% with clindamycin cut it 64%, no placebo arm at that dose (Pazoki-Toroudi 2011).
  • 20% is the highest concentration tested and approved, not a measured ceiling.

Is more than 15% azelaic acid better?

Nobody has measured it: no published dose comparison sets a ceiling for azelaic acid, so a percentage above 15% is above the trials' floor, not above a measured maximum. The highest dose tested in leave-on use was 20% (Bjerke 1999), and it was tolerated.

Local adverse events were transient and mainly mild or moderate, and rates were similar for azelaic acid cream (39.5%) and vehicle (38.5%).

The highest dose tested, in the paper’s words
  • Local adverse events were transient and mainly mild or moderate, and rates were similar for azelaic acid cream (39.5%) and vehicle (38.5%).

No published dose comparison sets a ceiling for azelaic acid. A declared percentage above 15% is above the trials' floor, not above a measured maximum: the trials say from 15% it works, and say nothing about whether more does more.

What does the azelaic acid percentage on a label tell you?

A name that states a percentage ("Azelaic Acid 15%") is the only amount a cosmetic label ever declares, so it is the one number that can be read against the trials: at or above the 15% floor, or below it.

A name without a percentage leaves the position. The rules make a brand list ingredients in descending order of amount down to 1%, and in any order below it, so azelaic acid above the 1% line is at least 1% and azelaic acid below it can be any trace the brand likes. The floor the trials worked from is 15%, and a position alone cannot tell you whether a label reaches it.

The azelaic acid percentages in our catalogue

The 2 products in our catalogue that carry azelaic acid: the number is the percentage the name declares, or the position on the label where it declares none. A rose mark is a declared percentage outside the range the trials used.

One label declares a percentage on the name, read against the trials:

One label carries it without a number, so the position is all there is:

Read on

Other actives with a dose the trials pinned:

The range column was researched and verified in September 2026 (this row last changed 27 September 2026). The number is the trials' and the reasoning is the knowledge base's; neither is advice about your skin. How we score.