Health Tips

How to Prevent High Altitude Illness using Medications?

Although hiking is a healthy activity, some reports stated that mountain climbers can suffer from high altitude illness(acute mountain sickness) when reaching areas of high altitude above 2500 meters. Symptoms of high altitude illness include headache, dizziness, nausea, loss of appetite, fatigue, swelling and sleeping problems. More severe consequences like swelling in the brain (cerebral edema) and lung (pulmonary edema) may develop if the mountain climbers are not being treated properly.

High altitude illness can be prevented by using medication. Acetazolamide is proven to be an effective medication in this aspect. It can stimulate breathing, improve air exchange and increase the oxygen level in the blood. It helps the body to adjust to the ascending altitude more easily. Acetazolamide not only prevents or minimizes the symptoms of high altitude illness, it also reduces the risk of cerebral and pulmonary edema.

Acetazolamide is usually started one day before the ascent and continued for a few days into the excursion. This medication, however, is not suitable for those who are allergic to sulfonamides, have G6PD deficiency and those who have poor kidney or liver function.

Apart from acetazolamide, steroid medication (dexamethasone) and calcium channel blocker (nifedipine) are also used in the management of high altitude illness. Dexamethasone is mainly used to reduce swelling in the brain while nifedipine is used in pulmonary edema.

In addition to taking preventive medication, mountain climbers also have dietary concerns. They are suggested to have regular meals with low calorie, low salt and high carbohydrate food. They should drink adequate fluid to replenish water loss. Alcohol, anxiolytic, hypnotic drugs and narcotic painkillers should be avoided. These medications can slow down breathing and therefore may reduce alertness on the symptoms of high altitude illness. They could be dangerous to mountain climbers.

In order to have a safe and enjoyable hiking trip, mountain climbers need to be well-prepared and bring along necessary medications. They should assess their physical strength objectively and also pay attention to their body condition.

Source: Drug Education Resource Centre, The Society of Hospital Pharmacists of Hong Kong