My First and Only Experience with Acute Mountain Sickness:

 

From 1989-1992 my family was living in Tokyo , Japan . In the summer of 1991 the local high school asked me if I would accompany a group of high school students (from the basketball and wrestling teams) on a summit of Mount Fuji . At the time I was known as a spots medicine guru and was in excellent physical condition. I agreed to go. To climb Mount Fuji , it is best to leave at 2:00PM-3:00 PM because it takes an un-acclimatized person about eight hours to reach the summit from the fifth station. One drives to the fifth station which is about 5000 ft in elevation, then you only need to climb another 7000 vertical feet to reach the summit at 12,388 ft. It was early August, one of the best times to climb as there is usually only snow at the very top. The base temperature was 72 degrees when we started at 3:00 PM . I took the lead, with one “guide” in the middle and one at the end of our group of about twenty students. We were advised about AMS before we left. I had plenty of water and food, but you really don't need it for Fuji as you can buy it on the way up at numerous “stations” where you can also get your climbing stick stamped. It's a social adventure climb and the people you encounter are very friendly and supportive. Everyone encourages the other and cooperates. It's that way in Japan . I did fine until I passed 10000 ft, then I developed a headache, nausea, loss of appetite and light-headedness. I had the feeling I had to vomit but nothing happened. It was cold, windy and dark with winds about 20-30 mph and the temperature was about 45 degrees. I found a sheltered place and forced myself to eat and drink and waited. After about 30-45 minutes the symptoms vanished as mysteriously as they appeared. I then proceeded at a slower pace and reached the summit at about 11:00 PM . It was 32 degrees with 40 mph winds at the summit. One advantage of getting to the summit early is that you could visit the Udon (really good Japanese noodles) Shop at the top. If you purchased noodles, the shop owner would let you sleep in the shop. This I did finding a nice resting place against a wall. I was awakened at about 5:30 AM the next day just before sunrise as the shop owner clanged two metal pots together to wake everyone so we would not miss the beautiful sunrise from Mount Fuji . It's no wonder Japan is called the Land of the Rising Sun. You really see why when you are at the summit. I never had any recurrent AMS symptoms and since 1995 have lived at elevations of 7000 ft in Park City and now Flagstaff . Even while mountain biking to the summit of Peak 10 (over 13000 ft) near Breckinridge two years ago I was fine. So I do think living at the higher altitudes is definitely preventive. The cause of AMS in my case was rapid ascent to over 9000ft, definitely overexertion and probably mild dehydration.