The only cure for mountain sickness is either acclimatisation or descent. Symptoms of Mild AMS can be treated with painkillers for headache, acetazolamide and Dexamethasone. These help to reduce the severity of the symptoms, but remember, reducing the symptoms is not curing the problem and could even aggravate the problem by masking other symptoms. Acetazolamide allows you to breathe faster so that you metabolise more oxygen, thereby minimising the symptoms caused by poor oxygenation, which is especially helpful at night when the respiratory drive is decreased.
Dexamethasone:
This powerful steroid drug can be a life saving element for people with HACO, and works by decreasing swelling and reducing the pressure in the skull. The dosage is 4 mg three times per day, and obvious improvement usually occurs within about six hours. This drug ‘buys time’, especially at night, when it may be too difficult to descend. Descent should be carried out the next day.
It is unwise to ascend while taking Dexamethasone: unlike Diamox, this drug only masks the symptoms. Dexamethasone can be highly effective: many people who are lethargic or even in coma will improve significantly after tablets or an injection, and may even be able to descend with assistance. Many pilgrims at the annual festival at Gosainkunda Lake in Nepal suffer from HACO following a rapid rate of ascent, and respond remarkably well to Dexamethasone.
Mountain climbers also sometimes carry this drug to prevent or treat AMS. It needs to be used cautiously, however, because it can cause stomach irritation, euphoria or depression. It may be a good idea to pack this drug for a high altitude trek for emergency usage in the event of HACO In people allergic to sulpha drugs (and therefore unable to take Diamox) Dexamethasone can also be used for prevention: 4 mg twice a day for about three days may be sufficient.
Other Medicines used for treating Altitude Sickness include: -
Ibuprofen, which is effective in relieving altitude induced headache. (600mg, three times a day) Nifedipine is usually used to treat high blood pressure. It rapidly decreases pulmonary artery pressure and also seems able to decrease the narrowing in the pulmonary artery caused by low oxygen levels, thereby improving oxygen transfer. It can therefore be used to treat HAPO, though unfortunately its effectiveness is not anywhere as dramatic that of Dexamethasone in HACO. The dosage is 20mg of long acting Nifedipine, six to eight hourly.
Nifedipine can cause a sudden lowering of blood pressure so the patient has to be warned to get up slowly from a sitting or reclining position. It has also been used in the same dosage to prevent HAPO in people with a past history of this disease. Frusemide may clear the lungs of water in HAPO and reverse the suppression of urine brought on by altitude. However, Frusemide can also lead to collapse from low volume shock if the victim is already dehydrated. Treatment dosage is 120mg daily.
Breathing! 100% Oxygen also reduces the effects of altitude sickness.
The Gamow Bag This clever invention has revolutionised field treatment of altitude sickness. The bag is composed of a sealed chamber with a pump. The casualty is placed inside the bag and it is inflated by pumping it full of air effectively increasing the concentration of oxygen and therefore simulating a descent to lower altitude.
In as little as 10 minutes the bag can create an "atmosphere" that corresponds to that at 900 to 1,500 metres (3,000 to 5,000 feet) lower. After two hours in the bag, the person's body chemistry will "reset" to the lower altitude. This acclimatisation lasts for up to 12 hours outside the bag, which should be good enough to get them down to a lower altitude and allow for further acclimatisation. The bag and pump together weigh about 6.5 kilos (15 pounds) and are now carried on most major high altitude expeditions. Bags can be rented for short-term treks or expeditions.
