The effect of fennel (Foeniculum vulgare) gel 3% in decreasing hair thickness in idiopathic mild to moderate hirsutism, A randomized placebo controlled clinical trial.

Background: Hirsutism is a common symptom presenting to primary care endocrinologists, gynecologists, and dermatologists. Management is usually a long and troublesome process. This study was designed to evaluate the effect of fennel topical gel on mild to moderate idiopathic hirsutism.

Methods: The randomized, double-blind, placebo-controlled clinical trial was carried out from 2009 to 2011, in Sari, Iran. Forty four women with mild to moderate idiopathic hirsutism were randomly divided to case and control groups, each group included 22 cases. The case group received fennel gel 3% and the control group received placebo. The effect of fennel gel 3% was defined as reduction of thickness of facial hair in micrometer by microscope in comparison with placebo. Measurements were performed at zero time and 24 weeks after treatment. This study was registered in the Iranian Registry of Clinical Trial (www.irct.ir) with registration number 138901213672N1.

Results: The mean age of patients was 26.9±6.7 and 25.6±4.3 years in case and control groups, respectively. Hair thickness was similar between the two groups before intervention. The hair thickness reduced from 97.9±31.5 to 75.6±26.7 micron in patients receiving fennel gel after 24 weeks (P<0.001). Four patients complained of itching (3 in case group) and 4 patients complained of irritation and itching (3 in case group). However, this difference was not statistically significant.

Conclusion: The study indicated that fennel gel 3% is effective in decreasing hair thickness in women with idiopathic mild to moderate hirsutism.