Altitude sickness in Colorado Springs and on Pikes Peak

Colorado Springs is my hometown, and the trip to the top of Pikes Peak is one of the first things visitors want to do. Altitude sickness is common, usually mild, and largely preventable if you plan for it. Here is what the CDC's travel medicine guidance says and how I'd plan a visit.

1. 14,115 ftPikes Peak summit. More than twice the height of Colorado Springs, and reachable by car, train or trail in a single day.
2. 8,000 ftWhere altitude sickness usually starts. About 1 in 4 visitors who sleep above this height in Colorado get it.
3. 6,035 ftColorado Springs. High enough to notice on a run, but below the usual threshold for sleeping.

What altitude sickness feels like

The common form is called acute mountain sickness. The main symptom is a headache, usually with at least one of these: loss of appetite, nausea or vomiting, dizziness, or fatigue. People often compare it to a hangover. It usually starts 2 to 12 hours after arriving at altitude, often during or after the first night.

The good news: if you don't go any higher, it usually clears up within 12 to 48 hours. Children get it as often as adults. In a toddler who can't tell you about a headache, look for a poor appetite, fussiness and pale skin.

Who gets it

Being fit does not protect you. Training and fitness don't change your risk, and men and women are affected about equally. The best predictor is how you did on past trips to a similar altitude at a similar pace. The other big factors are where you started and how fast you climbed. Flying in from sea level and heading straight up into the mountains is the classic setup.

How to prevent it

• Sleep low when you can. Staying in Colorado Springs and visiting the high country by day is easier than sleeping in a mountain town above 8,000 feet on your first night.
• Go up gradually. The CDC advises against going from below 4,000 feet to sleeping above 9,000 feet in a single day. If you are sleeping higher, spend two or three nights around 8,000 to 9,000 feet first.
• Take it easy for 48 hours. Avoid alcohol and keep exercise mild for your first two days at altitude. Save the big hike or hard race effort for later in the trip if you can.
• Keep your usual coffee. If you normally drink caffeine, keep drinking it. A caffeine-withdrawal headache is easy to mistake for altitude sickness.
• Ask about medicine before you go. A prescription medicine called acetazolamide can help prevent altitude sickness for people at higher risk or with a fast ascent. Talk with your doctor before your trip, since it isn't right for everyone.

If you have heart or lung disease, sleep apnea, diabetes, sickle cell trait, or you are pregnant, talk with your doctor before a trip to high altitude. Make sure any chronic condition is stable before you travel, and have a plan for what to do if it flares. If you use a glucose meter, check your sugar more often: some meters read less accurately at altitude.

When to go down

If you have symptoms, don't go any higher to sleep. Rest where you are, and if symptoms get worse despite rest, go down. Descending even 1,000 feet usually helps quickly. On Pikes Peak, that simply means starting the drive back down.

Two rare forms of altitude illness are emergencies:

• Swelling of the brain (HACE): confusion, unusual drowsiness, or trouble walking straight, as if the person were drunk.
• Fluid in the lungs (HAPE): a cough, chest congestion, and shortness of breath out of proportion to the effort, which can progress to breathlessness at rest.

Either one means go down right away and call 911. Don't wait to see if it passes.

If you're coming to town for a race or moving here to train, my guide for athletes and active adults covers training at altitude, and the Zone 2 note explains why heart rate is a better guide than pace up here.

Sources: Hackett PH, Shlim DR. High-altitude travel and altitude illness. CDC Yellow Book: Health Information for International Travel. 2026 edition. cdc.gov. U.S. Forest Service, Pike and San Isabel National Forests. Pikes Peak (summit elevation). fs.usda.gov. City of Colorado Springs, 2025 Budget, Springs at a Glance (elevation). coloradosprings.gov.