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Ginkgo biloba does--and does not--prevent acute mountain sickness.
Guy Leadbetter1, Linda E Keyes, Kirsten M Maakestad
1Department of Exercise Physiology, Mesa State College, Grand Junction, CO, USA.
Wilderness & Environmental Medicine
|April 15, 2009
Summary
The source of Ginkgo biloba extract (GBE) may impact its effectiveness in preventing acute mountain sickness (AMS). One study showed GBE reduced AMS, but another did not, highlighting the importance of GBE product composition.
Area of Science:
- Altitude sickness research
- Pharmacological interventions
- Herbal medicine efficacy
Background:
- Acute mountain sickness (AMS) affects individuals rapidly ascending to high altitudes.
- Ginkgo biloba extract (GBE) has been investigated for its potential prophylactic effects against AMS.
- Conflicting results exist regarding GBE's efficacy in preventing AMS.
Purpose of the Study:
- To evaluate the efficacy of two distinct Ginkgo biloba extract (GBE) sources in preventing acute mountain sickness (AMS).
- To assess the impact of GBE on both the incidence and severity of AMS after rapid high-altitude ascent.
Main Methods:
- Two randomized, double-blind, placebo-controlled cohort studies were performed.
- Participants received GBE (240 mg/day) or placebo before and during ascent from 1600m to 4300m.
- AMS diagnosis was based on Environmental Symptom Questionnaire III (AMS-C) and Lake Louise Symptom (LLS) scores, along with headache presence.
Main Results:
- GBE efficacy was source-dependent, with conflicting outcomes between the two studies.
- In the first study, GBE significantly reduced AMS incidence (P=.027) and severity (P=.029) compared to placebo.
- In the second study, GBE did not show a significant effect on AMS incidence (P=.247) or severity (P=.272).
Conclusions:
- The effectiveness of Ginkgo biloba extract for AMS prophylaxis may be contingent upon the specific source and composition of the GBE product.
- Further research is needed to identify the specific components responsible for GBE's potential benefits in AMS prevention.
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