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Evidence summaries

Acetazolamide for Preventing High Altitude Illness

Acetazolamide appears to reduce the incidence of acute altitude sickness compared with placebo. Level of evidence: "B"

The quality of evidence is downgraded by study limitations (unclear allocation concealment and detection bias).

Summary

A Cochrane review [Abstract] 1 included 64 studies with a total of 4547 subjects. The risk of acute mountain sickness (AMS) was reduced with acetazolamide (table T1). Few studies reported side effects for this comparison, and they showed an increase in the risk of paraesthesia with the intake of acetazolamide. For dexamethasone, there was a trend towards reduced acute mountain sickness, but it was insignificant.

Acetazolamide/dexamethasone compared with placebo for preventing high altitude illness

OutcomeRelative effect (95% CI)Assumed risk - PlaceboRisk with intervention - AcetazolamideNo of Participants (studies)
Incidence of acute mountain sicknessRR 0.47 (0.39 to 0.56)241 per 1000113 per 1000 (94 to 135)2301 (16)
Incidence of high altitude pulmonary oedema (HAPE)Not estimableNo events1138 (7)
Incidence of high altitude cerebral oedema (HACE)RR 0.32 (0.01 to 7.48)2 per 10001 per 1000 (0 to 14)1126 (6)
OutcomeRelative effect (95% CI)Assumed risk - PlaceboRisk with intervention - DexamethasoneNo of Participants (studies)
Incidence of acute mountain sicknessRR 0.6 (0.36 to 1)449 per 1000270 per 1000 (162 to 449)176 (4)

Clinical comments

Note

Date of latest search: 20th August 2018

    References

    • Nieto Estrada VH, Molano Franco D, Medina RD et al. Interventions for preventing high altitude illness: Part 1. Commonly-used classes of drugs. Cochrane Database Syst Rev 2017;(6):CD009761. [PubMed]

Primary/Secondary Keywords