Its a common problem in Tibet, and can be minimised.
There are numerous causes of altitude sickness, mostly to do with the rate of ascent and dehydration. Drink plenty of water and go slow! The precentage of oxygen in the air at higher altitudes is less than at lower temps - and apart from carrying a heavy oxugen tank there is little you can do to avoid this.
I also found chewing raw garlic helped and stopping a lot for a cup of tea. Mind you - ther result was I didnt get kissed too often on my trek! about 6 years ago
I haven't tried chewing garlic, but it would also be a good idea to take medication like diamox, which is a prescribed drug in some countries. Note that you will not be able to find diamox in China or Tibet, better ask your doctor for more advice.
I found most people traveling in Tibet are actually okay with the altitude. Then why do people always scared of the altitude before coming to Tibet? Because those who suffered from serious complication of mountain sickness will make the noisiest news. about 6 years ago
Altitude illness is real, not a myth. I recently travelled from Chengdu to Lhasa by train and it goes over mountains that are 5072m high. Altitude sickness starts at about 3000m or even lower for some. I struggled with it for a few days after getting off the train. I should have used the oxygen on the train to minimize the impact. There are some medicines available but they also have side effects. The previous persons advice re water and also do not exert yourself. about 6 years ago