Received: 18 November 2011                                                    Revised accepted: 27 July 2012

Purpose: To investigate the effect of Glycyrrhiza glabra root extract on hair growth in female Wistar rats.   

Methods: Female Wistar rats were used for the hair growth promotion studies. They were divided into three groups(n = 6) and their dorsal skin was completely denuded to completely remove hair. Paraffin oil (control), 2 % minoxidil solution (reference) or petroleum ether (60 – 80 ⁰C) root extract of G. glabra (2 %), was applied to the denuded skin once daily for 30 days. During this period, they were observed visually for hair growth and thereafter skin biopsy was taken for evaluation of follicular density and cyclic phases of hair growth.

Results: Animals treated with petroleum ether extract of G. glabra roots showed longer hair than those treated with either minoxidil or control. Furthermore, the time (5 – 13 days) for commencement of hair growth and to reach complete hair growth was least in  extract-treated animals, followed by those treated with minoxidil (6 - 19 days). A maximum  of 76 % of hair follicles were in anagenic stage (active growth phase of hair) in extract-treated animals, compared to 66 and 45 %  in minoxidil-treated and control groups, respectively.

Conclusion: This study indicates that the petroleum ether extract of G. glabra roots has potentials as a hair growth promoting agent for females.