What to Know About Altitude Sickness

Whether you’re hitting the slopes in the winter or the trail in the summer, you need to be prepared for altitude sickness, also known as acute mountain sickness (AMS). Although it’s normally just a nuisance, it can be very serious. And it will ruin the fun of a mountain vacation.

The Cause of Altitude Sickness

Essentially, altitude sickness is caused by reduced air pressure at altitude. Air pressure is basically the weight of the column of air that presses you from the ground to the top of the atmosphere. As you ascend, there’s less air around you, so the pressure drops.

You can likely notice the effect if you’re going from sea level to Littleton’s altitude of 5310 feet, but altitude sickness typically occurs only once you ascend to an altitude of 8,000 feet. For reference, the town of Breckenridge is about 9600 feet, and the top of some lifts are at nearly 13,000 feet.

Reduced air pressure makes it harder for oxygen to get into your blood. Not only will there be less oxygen in the same volume of air in your lungs, but lower air pressure hampers the gas exchange mechanism that your lungs use to put oxygen in your blood. This means that you may have less oxygen in your blood. The oxygen in your blood allows the cells of your body to use energy. Without oxygen, your cells die, and with reduced oxygen they are in distress.

Altitude sickness can cause a form of sleep apnea in otherwise healthy people, and it may worsen the effects of sleep apnea.

The Effects of Altitude Sickness

Many people describe altitude sickness as being like a hangover. You may experience:

  • Headache

  • Nausea or vomiting

  • Lack of appetite

  • Fatigue

  • Difficulty sleeping

  • Dizziness or vertigo

Sometimes altitude sickness can cause fluid to accumulate in your lungs or brain, which is serious. If you have severe light sensitivity, cannot sit up, struggle to breathe, or have an altered mental state, you should visit a doctor.

Preventing Altitude Sickness

There is really no way to prevent altitude sickness, and people of all health levels are potentially at risk. However, you can reduce your risk by following these tips:

  • Ascend gradually: if you’re coming from sea level, spend a day or two in Denver (or Littleton—you’re welcome out here) before heading up to the mountains

  • Do only mild exercise in the first 48 hours

  • Avoid alcohol in the first 48 hours (I know, most of us like to hit the bars at the ski resort—but you’ve been warned!)

  • If you’re doing multiple trips, put them within 30 days of each other—this will help you maintain acclimatization

  • If you have sleep apnea, don’t forget your CPAP or other treatment, and talk to your doctor about acetazolamide, which can help

Taking appropriate steps will improve the odds that you can enjoy your mountain vacation.

If you’re planning a mountain vacation and want to talk to a primary care doctor about it, please make an appointment with Dr. Andy Fine in Littleton.

Like this article?

Share on facebook
Share on Facebook
Share on twitter
Share on Twitter
Share on linkedin
Share on Linkdin
Share on pinterest
Share on Pinterest

Leave a comment

Family Medicine Conveniently Located in Littleton, CO


20 W Dry Creek Circle
Littleton, CO 80120


7:00am - 5:00pm
Mon - Fri


(303) 703-8583

Book Your Appointment

Scroll to Top