Cusco · Kilimanjaro · Everest Base Camp · the high Rockies
Acetazolamide is the CDC-backed way to blunt acute mountain sickness — prescribed online by a board-certified physician, at your pharmacy today. $49 flat.
Who needs it
CDC flags risk for anyone sleeping above ~8,000 ft — and strongly encourages prophylaxis above 11,000 ft or on fly-in arrivals like Cusco (3,339 m), where nearly half of travelers feel it in the first 48 hours.
How it works
125 mg twice daily, starting the day before ascent and through your first two days up high. It speeds the acclimatization your body would do anyway — think of it as a head start, not a shortcut.
What to expect
Tingly fingers and flat-tasting soda are normal and harmless. It never replaces sensible ascent — and we tell you exactly what "sensible" means for your route.
The prescription, precisely
Take 125 mg by mouth every 12 hours, beginning the day before ascent and continuing the first 2 days at altitude (longer if ascent continues). If body weight >100 kg: 250 mg twice daily.
Dosing per CDC Yellow Book 2026. Your physician confirms fit and quantity for your itinerary — nothing is issued automatically.
The honest part
Acetazolamide reduces risk — it doesn’t abolish it. Even medicated, roughly 40% of fast Kilimanjaro climbers feel some symptoms. If symptoms worsen at altitude, descent is the treatment, and your plan says so plainly.
$49 flat · reviewed by Adam Z. Kawalek, MD · full refund if we can’t help