There’s no other way to prepare for altitude than to acclimatize slowly. Our trek itineraries have been carefully planned to allow for gradual acclimatization (at Bhoj Kharak and Kedar Kharak). Altitude sickness can affect the fittest trekkers just as easily as the less fit. Once on the trek, the main recommendation is to keep your fluid intake up and stay hydrated. We don’t recommend Diamox(acetazolamide). Diamox actually tricks your body into breathing faster (by changing the Ph of your blood slightly) so it actually prevents the symptoms. The best cure for high altitude sickness is acclimatization.