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.
Department of Exercise Physiology, Mesa State College, Grand Junction, CO, USA.
Guy
G
Leadbetter
Linda E
LE
Keyes
Kirsten M
KM
Maakestad
Sheryl
S
Olson
Martha C
MC
Tissot van Patot
Peter H
PH
Hackett
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