As I learned the hard way, gaining altitude too fast can send you reeling—even kill you.

Even non fatal manifestations of altitude sickness are horrible: common symptoms include breathing problems, mind-numbing head pounding, frequent urination, dehydration, light headedness and poor judgment.
 

( In my case, one of the graver signs was a longing for a fast foot burguer Value Meal as I was staggering through the Peruvian Andes at something like 17,000 feet).
 
And yet, like so many of the more dangerous things human beings can do, there is no permit required for simply flying in to a high place.

If you’re planning to get really high—the mountains of Nepal or much of Machu Pichu, CUZCO, there is no substitute for time. Any mountain climbing guide will tell you to acclimate for days—even weeks—at a time at periodic elevations if you plan on gaining obscene amounts of ground on your trip to heaven.

When the headaches stop, when you can run 20 steps without seeing spots, you’re ready for the next plateau.

Modern medicine prescribes altitude medicines such as acetazolamide, dexamethasone and nifedipine—all of which require consultation with a doctor. I’ve actually brought some medication along on a trip or two. The problem is, when I really needed it, the label scared me off. It read, “take two tablets and descend.” I was in no position to descend, as it was after dark in about 5 million acres of Andean wilderness, and I didn’t know what the effect would be if I took the meds but didn’t descend. Head explosion? Rooting for the Cowboys? These weren’t risks I was willing to take.

I found out later that the medicine without the descent is better than no medicine at all, but that’s beside the point. Next time I’ll stick with time-honored “acclimation.” Any other tips for avoiding altitude sickness?

Doctors are now prescribing Diamox to be taken for a couple of days before going to altitude. It seems to work for me. I used to get mild altitude sickness (headache and nausea lasting about 24 hrs) each time I went to Vail, CO (which is at something like 7,000-8000 ft.). The last couple of times I've taken some prescription tabs and have had no symptoms. Also, tell people to drink plenty of water and avoid alcohol and caffeine for the first day or so.

A friend of my spent 12 days in LaPaz, Bolivia at 10,000'+. I did take 5 tablets of acetazolamide over 2 days, but I think what also helped is being in good cardiovascular shape, drinking lots of water, and avoiding strenuous physical activity most of the time I was there. I never got sick or had headaches, just some shortness of breath and tingling in my fingertips.

Eat small meals. Drink mate coca (coca tea) at least two times a day and/or chew coca leaves (if available). Avoid alchohol.
—Damiel Sandman

A very healthy way to fight altitude sickness is to drink four times a day during two consecutive days an infusion of coca leaves (MATE COCA). This beverage can be easily prepared using small tea bags.