How to Treat and Prevent Altitude Sickness

Home » Planning » Camp » How to Treat and Prevent Altitude Sickness


Backpacking is a hobby that’s done almost exclusively in the mountains – or at the very least, at a higher elevation than many of us are used to. While it’s great for a change in scenery, and exciting trails to navigate, many of us enter this space without considering one particular, unseen enemy.

Altitude sickness is often thought of as nothing more than an uncomfortable feeling that goes away on its own. You get a headache, feel a little nauseous, and then make a full recovery within a matter of hours.

But what if you don’t get better? What if it just keeps getting worse instead? And is there any way to know how to prevent altitude sickness in the first place?

Actually, there is.

Here’s everything you need to know.

What Causes Altitude Sickness?

woman hiking red backpack green mountains

Altitude sickness is caused by a decreased amount of oxygen circulating in the bloodstream. Most people will be fine up to 8,000 feet, but after this threshold, some may start to feel the effects of the higher elevation. In fact, about 20% of all adventurers travelling at an elevation between 8,000 and 18,000 feet will experience some degree of altitude sickness. Above 18,000 feet, that number increases to 50%.

Types of Altitude Sickness

There isn’t just one type of altitude sickness. While one is certainly more common than the others, there are three different variations that can affect you:

1. Acute Mountain Sickness (AMS)

man hiking red coat nepal himalayas mountains

Occurring most frequently, AMS is generally considered to be the least dangerous form of altitude sickness. Symptoms are similar to being intoxicated, and usually go away on their own as you get acclimated or return to a lower altitude.

2. High-Altitude Cerebral Edema (HACE)

HACE is a severe form of acute mountain sickness, usually developing if AMS is left untreated. The brain starts to swell, and it stops functioning normally, causing symptoms like confusion, drowsiness, and trouble walking. In some cases, it could even lead to death.

3. High-Altitude Pulmonary Edema (HAPE)

Often a progression of HACE, it’s still possible for HAPE to occur on its own. With it, your lungs will start to swell and accumulate fluid, making it difficult to breathe. You may also experience severe coughing and weakness. If left untreated, it is also possible for this form of altitude sickness to lead to death.

Symptoms of Altitude Sickness

man holding head red jacket blue backpack

The symptoms of altitude sickness can vary, depending on which form you have. Here are a few of the most common symptoms for each of them:

Acute Mountain Sickness: You’ll most often experience headache, nausea, vomiting, lethargy, fatigue, difficulty sleeping, and a loss of appetite. I’ve also found that an increased heart rate is quite common, and it’s something I mostly notice at night.

Those are the mild symptoms, and they should work as a stop sign, telling you that it’s a bad idea to keep climbing. If you decide to ignore what your body is telling you, it’s likely that you’ll start to develop more severe symptoms over time. These include more intense versions of the symptoms already listed, as well as chest tightening, coughing, confusion, seeing double, and feeling out of breath, even when you aren’t doing anything.

High-Altitude Cerebral Edema: In a lot of ways, you may feel like you’re drunk. It will be pretty much impossible for you to balance on one leg, or walk in a straight line, especially if you’re trying to go heel-to-toe. Don’t take this one lightly.

High-Altitude Pulmonary Edema: As we’ve mentioned, your lungs will start to fill with fluid if you develop HAPE. You may experience a wet, gurgly cough, and the shortness of breath will likely become unbearable. You’ll also have trouble finding the energy to do anything.

How to Prevent Altitude Sickness

I’m sure none of those symptoms sound very pleasant to you. But don’t worry, even if you have a history of developing altitude sickness, you don’t have to live with discomfort that comes with it. Here are just a handful of tips that you can follow to reduce or eradicate the symptoms of altitude sickness:

1. Drink Water

glass water bottle mountains blue sky

And a lot of water, at that.

You see, every time you breathe, you’re losing water in the form of vapor as it exits your lungs. When you’re at a high elevation, you lose water twice as fast this way, making it very easy to get dehydrated. As you continue to lose water, your blood volume decreases, minimizing the amount of oxygen that can be carried through your vessels. And since there’s less oxygen to take in at higher altitudes, you need to give your body all the help it can get.

Staying hydrated is one of the best ways to improve symptoms of AMS, aside from descending to a lower altitude. Try to drink at least the equivalent of one gallon of water each day if you’re going to be fairly sedentary. You’ll want more than that (between 1.5 and 2 gallons of water) depending on how active you plan on being during the day, and how hot the weather ends up being.

2. Climb Slowly

Don’t push your body more than you need to. Especially if you’re coming from a place close to sea level, it’s important to avoid starting your journey above 10,000 feet. You’ll need the time to adjust, so try not to ascend more than 1,000 feet a day as well.

When I was backpacking through Nepal, there was a specific day where I started at 8,000 feet and ended at 15,000 feet. Trust me when I say that it was one of the most awful experiences of my life, between the extreme fatigue and altitude sickness. Granted, climbing 7,000 feet in one day is pretty unusual, but even so, don’t rush your ascent. Your body will thank you for it.

3. Take the Time to Acclimate

people hiking dirt trail sunshine mountains

As we just mentioned, going from sea level to an altitude above 10,000 feet is something you should avoid doing right away. Acclimation is the process of getting used to a higher elevation, and when done correctly, it can often prevent you from experiencing any altitude sickness at all.

Generally speaking, it takes about 24-48 hours for a person to acclimate. Because of this, it isn’t ideal to fly or drive to a higher elevation quickly, since it doesn’t give your body the proper amount of time needed to adjust. If possible, take your ascent slowly, slotting in a rest day after every 3,000 feet of elevation gain.

Well, that’s the recommendation at least. In actuality, I know it’s often hard to be so accommodating, and you’ll likely be driving or flying straight to a higher altitude. In cases like these, you probably won’t have the luxury to get properly acclimated before you begin your journey. However, to prevent severe cases of altitude sickness from setting in, you should still prioritize resting those first 24 hours. Just stay in one place without moving around too much, so your body can do its best to acclimate.

4. Avoid Alcohol and Tobacco

Though relatively little research has been done on this topic, there is some evidence to suggest that alcohol can exacerbate the effects of altitude sickness. Certain Austrian studies have indicated that drinkers tend to have a harder time breathing at higher altitudes compared to non-drinkers. They may also experience a spike in blood pressure.

On top of that, we know that smoking is hard enough on your lungs as it is. When combined with high elevation and dehydration, you could be putting yourself in a dangerous situation if you decide to smoke during your trip.

5. Eat more Carbs

I bet you never thought you’d be told to eat more carbs for the sake of your health! But here we are.

Carbs break down into sugar, which can be a double-edged sword. Sugar is used for energy, which is great when you’re hiking at higher elevations, but it’s bad for your health if you’re living a sedentary life. However, the other benefit of carbs is that they take less oxygen to break down, especially when compared to fat. So, make sure to pack plenty of bread, pasta, and other items rich in potassium to give you the energy you need.

Read More: Backpacking Meals to Give you Energy During the Day

6. Sleep at Lower Elevations

woman orange tent mountains sunrise camping

There’s a popular hiking motto that says, “Climb high, sleep low.” This is because altitude sickness gets worse at night while you’re sleeping, so you’ll want to take extra precautions during this time.

If possible, find a good place in the valley to set up camp for the night. Or at the very least, make sure your campsite isn’t at the highest location you reached that day. It doesn’t matter as much if you only ascended 1,000 feet or less in the last 24 hours, but if you made it past that threshold, it’s important to find a lower place to sleep.

7. Use Medication

Medication can help reduce or eliminate the symptoms of altitude sickness. In particular, acetazolamide (otherwise known as Diamox) has been shown to be fairly effective in this regard.

However, you will need a prescription in order to get acetazolamide, as it is a medication used to treat glaucoma. Taking it two days before your trip, and during your time at altitude, may be effective at reducing the severity of AMS. On the other hand, if you start developing symptoms anyway, taking more of the medication won’t make you feel better. At that point in time, the only thing that will help is hiking down to a lower elevation.

Treating Altitude Sickness

Overall, the best treatment is always going to be bringing yourself to a lower elevation. If you have advanced symptoms of AMS, HACE, or HAPE, seek professional medical attention immediately.

However, if you feel like you’re only experiencing mild symptoms and you aren’t able to descend easily, there are other ways you can cope. Ibuprofen can help with the headache, and thoroughly hydrating yourself can also work to relieve various symptoms.

In more extreme cases, you may be prescribed acetazolamide to help improve labored breathing. Dexamethasone is a steroid that can also be effective for this purpose. Lung inhalers, pure oxygen, and high blood pressure medication can reduce the pressure on your lungs, allowing you to breathe somewhat easier. However, you may need to be put on a breathing machine if you’re having enough difficulty doing it on your own.


Spencer Yeomans

Spencer Yeomans

A lover of the outdoors, and especially the mountains, Spencer has always enjoyed pushing people to step outside their comfort zones. His mission is to help others get out of their homes, push their limits, and to have fun staying active in nature.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top