Effect of Ginkgo biloba extract on plasma steroid concentrations in healthy volunteers: a pilot study.
OBJECTIVE
To determine if a standardized ginkgo supplement significantly alters concentrations of circulating androgenic steroids in humans.


METHODS
Open-label, fixed-treatment order, crossover study.


METHODS
University general clinical research center.


METHODS
Eleven healthy volunteers (six men, five women).


METHODS
Volunteers received ginkgo biloba 240 mg/day for 14 days.


RESULTS
Plasma concentrations of cortisol, 11-deoxycortisol, 17alpha-hydroxyprogesterone, testosterone, dihydrotestosterone, dehydroepiandrosterone sulfate, sex hormone-binding globulin, androstenedione, and free testosterone, as well as free androgen index and combined concentrations of androsterone sulfate and epiandrosterone sulfate, were analyzed in all subjects before and after their 14-day course of ginkgo biloba. Ginkgo biloba did not significantly alter endogenous steroid levels compared with baseline values (p < 0.05).


CONCLUSIONS
A 14-day oral administration of a widely used, standardized ginkgo extract at a generally advocated dosage of 240 mg/day did not significantly alter concentrations of major circulating steroids in men and women.
Markowitz
John S
JS
Department of Pharmaceutical Sciences, Medical University of South Carolina, Children's Research Institute, Charleston, South Carolina 29425, USA. markowij@musc.edu
DeVane
C Lindsay
CL
Lewis
John G
JG
Chavin
Kenneth D
KD
Wang
Jun-Sheng
JS
Donovan
Jennifer L
JL
D000328:Adult; D000735:Androstenedione / Q000097:blood; D018592:Cross-Over Studies; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood; D013196:Dihydrotestosterone / Q000097:blood; D005260:Female; D020441:Ginkgo biloba; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D010865:Pilot Projects; D010936:Plant Extracts / Q000494:pharmacology*; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013256:Steroids / Q000097:blood*; D013739:Testosterone / Q000097:blood; D000096983:Ginkgo Extract
D000735:Androstenedione; D019314:Dehydroepiandrosterone Sulfate; D013196:Dihydrotestosterone; D006854:Hydrocortisone; D010936:Plant Extracts; D012738:Sex Hormone-Binding Globulin; D013256:Steroids; D013739:Testosterone; C063170:Ginkgo biloba extract; D000096983:Ginkgo Extract