The first rule of treatment for mild symptoms of acute mountain sickness is to stop ascending until your symptoms are completely gone. If you have more severe symptoms or any symptoms of high-altitude cerebral edema, high-altitude pulmonary edema, or blurred vision, you need to move to a lower altitude as soon as possible, even if it's the middle of the night. If you remain at your current altitude or continue going higher, the symptoms will get worse and the sickness can be fatal.
Besides moving to a lower altitude, you can treat mild altitude sickness with rest and pain relievers. The drug acetazolamide can speed recovery. This drug balances your body chemistry and stimulates breathing.
If you have symptoms of altitude sickness, avoid alcohol, sleeping pills and narcotic pain medications. All of these can slow your breathing, which is extremely dangerous in low-oxygen conditions.
Besides moving to a lower altitude — or if a descent must be delayed — you can treat high-altitude cerebral edema with supplemental oxygen and the drug dexamethasone, which decreases brain swelling. If one is available, this condition is also helped by time spent in a portable hyperbaric (pressure) chamber, which simulates descent to a lower altitude, during the time that supervision and transportation arrangements are being made for descent to lower altitude. Additional treatment for high-altitude pulmonary edema includes oxygen and nifedipine, as well as the use of a standard hyperbaric chamber.