Altitude sickness

I am going walking in the foothills of the Himalayas and I hear a lot about altitude sickness. Can anyone advise me on what to do to combat it. Also, will I need special clothes?

 If walking in the Himalayas, think about sourcing some coca leaves. I know when I walked in the Andes they were widely used, especially in tea, as a cure/preventative for altitude sickness. Drink as much coca tea as you can get, if you find some there!
Fiona McCann

 Altitude sickness (or acute mountain sickness) is caused by the body's failure to adjust to the shortage of oxygen in the air at high altitude. It is potentially fatal and yet entirely preventable. The key is to gain height slowly, stop to rest if symptoms emerge and return to a lower altitude if symptoms persist.

Between 2,000m and 3,000m, at least two nights should be spent acclimatising. Above 3,000m, the net altitude gain per day should not exceed 300m, and a further rest day should be taken every 900m. You can ascend higher during the day, but you should respect the guidelines for daily net gain by returning to a lower level to sleep. It is also important to drink plenty of fluids and avoid alcohol.

Symptoms of mild AMS include headaches, nausea, dizziness, appetite-loss and a dry cough. If you experience these, stop and rest overnight at the same (or lower) altitude. Do not gain more altitude until symptoms have disappeared. Symptoms of serious AMS include persistent severe headache, persistent vomiting, ataxia, loss of consciousness, bloody or watery cough, difficult or rapid breathing, severe lethargy or worsening of the symptoms of mild AMS. If serious AMS develops, descend immediately.
James Rampton

 Acetazolamide (Diamox), is a diuretic medicine that alters the acidity of the blood and stimulates an increase in breathing rate, thereby increasing oxygen availability and speeding acclimatisation. It is available cheaply over the counter in Kathmandu/ Pokhara. I use two 250mg tablets in the morning beginning 2-3 days before ascent and continue until I'm on my way down. The downsides are that it makes you pee more than usual and can give you some tingling in the hands and feet.
Dr Matthew Ellis