Climbazole: what the evidence shows for dandruff and flaking scalp
Climbazole is an azole antifungal used in anti-dandruff shampoos, usually alongside another active. Here is what the trials show and how CSL formulation scientists use it within the EU limits.
By CSL Formulation team · Evidence checked by CSL scientists
At a glance
- What it is
- An azole antifungal used in anti-dandruff shampoos and as a preservative
- Main benefits
- Fewer visible flakes and less itch, especially when combined with another anti-dandruff active
- Levels tested in trials
- 0.45% to 0.65%, mostly with zinc pyrithione or piroctone olamine
- Time to results
- 4 to 5 weeks in clinical studies
- Watch for
- EU limit of 2% in rinse-off anti-dandruff shampoo, lower preservative limits, few recent trials
01What is it?
Climbazole is an azole antifungal, related to ketoconazole, used in cosmetic anti-dandruff shampoos. It is rarely used alone; most products pair it with piroctone olamine or, outside the EU, zinc pyrithione. It can also act as a preservative at lower levels.
02What it does
Like other azoles, climbazole targets Malassezia, the scalp yeast linked to dandruff. In shampoos it reduces visible flakes and itch over a few weeks. Combination products appear to outperform single actives, but formula design matters as much as the actives chosen.
03The evidence
Studies below were checked against the publisher, DOI or journal record on 26 Sep 2026. We list design and size so you can judge the strength of each result.
| Study | Design | Who and how long | What it found |
|---|---|---|---|
| Turner et al. 2013, International Journal of Cosmetic Science (Wiley) Source | Half-head clinical comparison plus lab testing | 69 adults with dandruff, 4 weeks' use plus 2-week regression; 1% zinc pyrithione with 0.5% climbazole | The dual-active shampoo reduced visible flakes more than the comparison shampoo (P<0.002) and kept its lead after use stopped (P<0.001). Manufacturer study. |
| Schwartz et al. 2013, International Journal of Cosmetic Science (Wiley) Source | Randomised, double-blind clinical trial | 620 adults with dandruff, 4 weeks; an optimised ('potentiated') zinc pyrithione shampoo versus a zinc pyrithione/climbazole shampoo | The optimised zinc pyrithione shampoo reduced flaking more at every weekly visit, showing that the base formula matters as much as adding a second active. Manufacturer study. |
| Schmidt-Rose et al. 2011, International Journal of Cosmetic Science (Wiley) Source | Split-head comparison with in-use testing | Adults with moderate-to-severe dandruff, 4 weeks; 0.5% piroctone olamine plus 0.45% climbazole versus 1% zinc pyrithione | The piroctone/climbazole shampoo reduced dandruff as well as 1% zinc pyrithione; 90% of users reported less itch after 4 weeks. |
| Rastegar et al. 2009, Iranian Journal of Dermatology Source | Double-blind randomised trial | 120 men aged 20–30 with dandruff, 5 weeks, three washes a week; herbal shampoo with climbazole versus the same base with piroctone olamine (exact levels not clearly reported) | Complete clearance in 80% with climbazole versus 55% with piroctone olamine (p = 0.0063); itch and redness resolved in both groups. |
| Wigger-Alberti et al. 2001, Praxis Source | Open study, no control group | 30 adults with moderate-to-severe scalp seborrhoeic dermatitis, 1-week washout then 4 weeks; 0.65% climbazole shampoo | Dandruff, redness and itch clearly improved in 80% and mildly in 20%; cosmetic acceptability rated very good. |
Climbazole helps reduce visible dandruff, and adding it to another active can boost results. But the trials are small or old, mostly company-funded, and one large trial showed an optimised single-active shampoo beating a climbazole combination. Keep claims to "helps reduce visible flakes" and support them with testing on the finished product.
04How CSL formulation scientists use it
- For anti-dandruff use in the EU, the limit is 2% in rinse-off shampoo; trials used 0.45% to 0.65%.
- As a preservative, the EU limits are lower: 0.5% in rinse-off shampoo and 0.2% in face creams, hair lotions and foot care. Annex V lists no other product types for preservative use.
- Combine with piroctone olamine for a broader antifungal effect, and check deposition and in-use performance of the full formula.
- Include the Annex III label warnings where required and check scalp tolerance; mild irritation is possible.
05Regulatory and claims
Commission Regulation (EU) 2019/698 sets climbazole limits in Regulation (EC) No 1223/2009: Annex III entry 310 allows up to 2% in rinse-off anti-dandruff shampoo; Annex V entry 32 allows up to 0.2% in hair lotions, face creams and foot care and 0.5% in rinse-off shampoo as a preservative. These follow SCCS opinion SCCS/1590/17. Climbazole is not in the US OTC dandruff monograph (21 CFR 358.710), so US drug claims cannot rest on it. CSL regulatory specialists confirm the status in each other target market.
06Questions brands ask
Is climbazole better than piroctone olamine?
One randomised trial found a climbazole shampoo cleared dandruff in more users than the same base with piroctone olamine (80% vs 55%). Most brands combine the two.
Can climbazole be used in leave-on scalp products?
In the EU only as a preservative, up to 0.2% in hair lotions. The 2% anti-dandruff limit applies only to rinse-off shampoo.
Is climbazole a good zinc pyrithione replacement in the EU?
It is one of the main options, usually with piroctone olamine. Performance depends on the whole formula, so test the finished shampoo.
07References
- Turner GA, Matheson JR, Li G-Z, Fei X-Q, Zhu D, Baines FL. Enhanced efficacy and sensory properties of an anti-dandruff shampoo containing zinc pyrithione and climbazole. Int J Cosmet Sci. 2013;35:78–83. Link
- Schwartz JR, Bacon RA, Shah R, Mizoguchi H, Tosti A. Therapeutic efficacy of anti-dandruff shampoos: a randomized clinical trial comparing products based on potentiated zinc pyrithione and zinc pyrithione/climbazole. Int J Cosmet Sci. 2013;35(4):381–387. Link
- Schmidt-Rose T, et al. Efficacy of a piroctone olamine/climbazol shampoo in comparison with a zinc pyrithione shampoo in subjects with moderate to severe dandruff. Int J Cosmet Sci. 2011. Link
- Rastegar et al. A comparison of clinical efficacy between a basic shampoo with herbal extracts containing climbazole and its similar sample containing piroctone olamine in the treatment of dandruff and seborrheic dermatitis. Iran J Dermatol. 2009;12(3):82–85. Link
- Wigger-Alberti W, Kluge K, Elsner P. Clinical effectiveness and tolerance of climbazole containing dandruff shampoo in patients with seborrheic scalp eczema. Praxis. 2001;90(33):1346–1349. Link
- Commission Regulation (EU) 2019/698 of 30 April 2019 amending Annexes III and V to Regulation (EC) No 1223/2009 on cosmetic products. Link
- SCCS. Addendum to the opinion on climbazole (P64). SCCS/1590/17, 24–25 October 2017. Link
- US Code of Federal Regulations. 21 CFR 358.710: Active ingredients for the control of dandruff, seborrheic dermatitis, or psoriasis. Link
Used in: Dandruff & scalp health
Update log
- Evidence reviewed and page published by CSL scientists
This page summarises published research for brands and formulators. It is general information, not medical advice, and results in studies depend on the full formula tested.
