Ginkgo biloba does--and does not--prevent acute mountain sickness.
OBJECTIVE
To determine the efficacy of 2 different sources of Ginkgo biloba extract (GBE) in reducing the incidence and severity of acute mountain sickness (AMS) following rapid ascent to high altitude.


METHODS
Two randomized, double-blind, placebo-controlled cohort studies were conducted in which participants were treated with GBE (240 mg x d(-1)) or placebo prior to and including the day of ascent from 1600 m to 4300 m (ascent in 2 hours by car). Acute mountain sickness was diagnosed if the Environmental Symptom Questionnaire III acute mountain sickness-cerebral (AMS-C) score was > or =0.7 and the Lake Louise Symptom (LLS) score was > or =3 and the participant reported a headache. Symptom severity was also determined by these scores.


RESULTS
Results were conflicting: Ginkgo biloba reduced the incidence and severity of AMS compared to placebo in the first but not the second study. In the first study, GBE reduced AMS incidence (7/21) vs placebo (13/19) (P = .027, number needed to treat = 3), and it also reduced severity (AMS-C = 0.77 +/- 0.26 vs 1.59 +/- 0.27, P = .029). In the second study, GBE did not reduce incidence or severity of AMS (GBE 4/15 vs placebo 10/22, P = .247; AMS-C = 0.48 +/- 0.13 vs 0.58 +/- 0.11, P = .272). The primary difference between the 2 studies was the source of GBE.


CONCLUSIONS
The source and composition of GBE products may determine the effectiveness of GBE for prophylaxis of AMS.
Leadbetter
Guy
G
Department of Exercise Physiology, Mesa State College, Grand Junction, CO, USA.
Keyes
Linda E
LE
Maakestad
Kirsten M
KM
Olson
Sheryl
S
Tissot van Patot
Martha C
MC
Hackett
Peter H
PH
D000293:Adolescent; D000328:Adult; D000532:Altitude Sickness / Q000453:epidemiology / Q000473:pathology / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D020441:Ginkgo biloba / Q000737:chemistry*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009051:Mountaineering; D008517:Phytotherapy; D010936:Plant Extracts / Q000032:analysis / Q000494:pharmacology*; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult
D010936:Plant Extracts