If you’ve ever felt a headache, nausea, or shortness of breath after climbing just a few thousand feet, you’ve probably experienced mountain sickness. Also called altitude illness, it happens when your body can’t get enough oxygen at higher elevations. The good news is that most cases are mild and easy to handle if you recognize them early.
The first sign is usually a headache that doesn’t go away with painkillers. You might also feel dizzy, nauseous, or unusually tired. Some people get trouble sleeping, loss of appetite, or swelling in their hands and feet. If you notice these symptoms within the first 24‑48 hours after gaining altitude, take them seriously.
More severe forms include high‑altitude cerebral edema (HACE) – confusion, clumsiness, or even hallucinations – and high‑altitude pulmonary edema (HAPE) – extreme shortness of breath, coughing up pink frothy sputum, and a feeling of drowning. These are medical emergencies; you need to descend immediately and seek professional help.
The simplest prevention trick is to climb slowly. Gain no more than 1,000 feet (about 300 meters) per day once you’re above 8,000 feet, and take a rest day every few days. Staying hydrated helps because dehydration makes symptoms worse; aim for about 3 liters of water daily, but avoid alcohol and caffeine.
Eating high‑carb meals gives your body extra energy to adapt. If you’re prone to sickness or planning a rapid ascent, talk to a doctor about medication like acetazolamide (Diamox). A typical dose is 125 mg twice a day starting one day before the climb; it speeds up breathing and reduces fluid buildup.
When symptoms appear, the first step is to stop gaining altitude. Rest at your current level for several hours, drink water, and consider over‑the‑counter pain relievers for headaches. If you feel better after a few hours, you can continue climbing very slowly. If symptoms persist or get worse, descend at least 1,000 feet (300 m) as quickly as safely possible.Oxygen tanks are handy on popular high trails; a short burst of supplemental oxygen can relieve breathing trouble while you decide whether to go down. In remote areas, portable hyperbaric chambers provide an alternative way to increase pressure around you and ease symptoms.
Remember, mountain sickness is your body’s warning sign. Ignoring it puts you at risk for serious complications. By moving gradually, staying hydrated, eating right, and carrying a basic medical kit, you can enjoy high‑altitude adventures without the nasty side effects.