Topical Cyperus rotundus essential oil for treatment of axillary hyperpigmentation: a randomized, double‐blind, active‐ and placebo‐controlled study

The oil of the grass Cyperus rotundus (purple nutsedge) is an effective and safe treatment option for a variety of conditions. It has anti-inflammatory and antipigmenting properties. There have been no clinical trials comparing topical C. rotundus oil with skin-lightening treatments for axillary hyperpigmentation.To assess the efficacy of C. rotundus essential oil (CREO) in treating axillary hyperpigmentation, and compare with another active treatment hydroquinone (HQ) and a placebo (cold cream) in this study.The study included 153 participants, who were assigned to one of three study groups: CREO, HQ group or placebo group. A tri-stimulus colorimeter was used to assess pigmentation and erythema. Two independent experts completed the Physician Global Assessment, and the patients completed a self-assessment questionnaire.CREO had significantly (P < 0.001) better depigmenting effects than HQ. CREO and HQ did not differ significantly in terms of depigmentation effects (P > 0.05); however, there were statistically significant differences in anti-inflammatory effects and decrease in hair growth (P < 0.05) in favour of CREO.CREO is a cost-effective and safe treatment for axillary hyperpigmentation.