When you climb above 8,000 feet, your body doesn’t get enough oxygen—this is altitude sickness, a condition caused by low oxygen levels at high elevations that can lead to headaches, nausea, and in severe cases, life-threatening fluid buildup in the lungs or brain. Also known as mountain sickness, it doesn’t care how fit you are. Even elite athletes can get hit hard if they move too fast. It’s not just for climbers. People flying into places like Denver, La Paz, or Cusco often wake up feeling awful because their bodies didn’t have time to adjust.
The real problem is hypoxia, a state where tissues don’t get enough oxygen. Your body tries to fix this by breathing faster and pumping more blood, but if you rise too quickly, it can’t keep up. That’s where acclimatization, the slow process of your body adapting to lower oxygen levels comes in. Skipping this step—like flying straight to 10,000 feet and hitting the trails—is asking for trouble. Symptoms usually show up 6 to 24 hours after reaching high altitude. Mild cases mean headache, dizziness, and tiredness. Severe cases? Fluid in the lungs (HAPE) or brain (HACE), both need immediate descent and medical help.
You don’t need to be an expert to avoid this. Slow ascents, staying hydrated, and avoiding alcohol make a huge difference. Some people take acetazolamide to help their body adjust faster. Others just wait a day before hiking. The key is listening to your body. If you feel off, don’t push it. Many people ignore early signs because they think it’s just jet lag or a cold. It’s not. Altitude sickness is real, predictable, and preventable.
The posts below cover related topics you might not expect—like how certain medications affect your body at high altitudes, what supplements help with oxygen use, and how conditions like asthma or high blood pressure change your risk. Whether you’re planning a trek in the Andes, moving to a mountain town, or just curious why you feel awful after a flight to Colorado, you’ll find practical, no-fluff advice here.
Acetazolamide helps manage chronic respiratory acidosis by correcting the body's chemical imbalance, not by improving breathing. Learn how it works, when it's used, and what to watch for.