Last summer, we went on a vacation out to visit Rocky Mountain National Park in Colorado to get some fresh mountain air. As my son and I climbed up to the summit of an 11,000 foot peak, I felt awesome. Sure, I was winded a little bit easier, but otherwise it was a spectacular climb.

A month later, I hiked up to the summit of Pike’s Peak topping out at 14,115 feet. My breathing was definitely more labored the closer I got to the summit, and I started to feel a little nauseated. I quickly blamed my symptoms on overexertion and not drinking enough water during the ascent.

Yet somewhere in the back of my mind, there was a little bit of a worry nagging at my psyche. Did getting lightheaded on Pike’s Peak mean I going to be prone to altitude sickness during my upcoming Kilimanjaro ascent? I was beginning my trip from Kansas City, which is a mere 900′ feet above sea level. Would body be more prone to altitude issues coming from a such a low elevation?

What is altitude sickness?

Altitude sickness is side effect of ascending to higher elevations too rapidly. As you climb higher, you’ll experience diminishing oxygen levels in the air. This can lead to headaches, nausea, fatigue, vomiting, dizziness, or even death in some cases.

Altitude sickness typically only occurs above elevations of 8,000 feet. The higher you ascend and the more rapidly you do so, the greater the risk you’ll be affected by altitude sickness.

Climbers who ascend above 13,000 feet have a much higher risk of feeling altitude sickness. And climbers who ascend above 18,000 feet are at the highest risk for problems.

Altitude sickness isn’t an ‘all or nothing’ event. It’s best to think of it on a spectrum. Acute Mountain Sickness (or AMS) is the mildest form, and usually presents itself as headaches, shortness of breath, and other minor symptoms. Returning to a lower elevation or slowing your ascent usually causes these symptoms to subside.

However, if you continue to ascend without heeding these symptoms, your altitude sickness can progressively get worse. And it may even result in swelling in your brain or fluid in your lungs – both of which can be fatal events.

Symptoms of this severe altitude sickness can be scary, and may include disorientation, decreased coordination, severe headaches, vomiting, inability to walk, or even hallucinations.

Preventing altitude sickness

Clearly getting sick on a mountain is not something I want to add to my Kilimanjaro expedition. The summit is at 19,341 feet elevation, so it was in the “highest risk” zone. So how could I go about preventing the side effects of climbing to such a high elevation?

The best way to combat altitude sickness is to ascend slowly so your body has time to acclimate to its surroundings.

Responsible guides develop a plan to take climbers to higher elevations at a controlled and relaxed pace. While this might be frustrating for the climber who eagerly anticipates reaching the summit, it’s the safest way to acclimate to any high altitude.

In addition to ascending slowly, most guides practice the principle of “Climb HIGH, Sleep LOW.”

This means you ascend to higher elevations for a few hours during the day to let your body experience a little of it. Then you return back down to a lower elevation to sleep and recover. You’re essentially testing the waters, so to speak, without committing to jumping into the deep end.

Other things that can help aid acclimatization, in conjunction with these two methods, are:

  • Staying well-hydrated
  • Not overexerting yourself while gaining altitude
  • Avoiding alcohol or drugs while climbing

What about Diamox?

As I learned more about altitude sickness, I discovered a lot of climbers recommended Diamox as an additional way to diminish the risks.

Diamox (or acetazolamide) is a medication that helps prevent altitude sickness. It doesn’t mask the symptoms you feel as you ascend. Instead it helps treat the underlying issue.

When taken properly, Diamox stimulates your kidneys to make more biocarbonate in your urine, thereby making your blood more acidic. This change in the pH level allows your blood to absorb more oxygen, thereby speeding up your acclimatization process.

Of course, like all medications, there are some side effects to consider. The most noticeable impact being its diuretic effect. You will have to pee A LOT – which will be another reasons for you to stay well-hydrated during your climb.

Given that I normally lived and exercised at such a low elevation, I wanted to give myself the best chance possible to summit Kilimanjaro. This meant:

  • Choosing guides who will lead my on my climb responsibly, and with a gradual ascent
  • Opting for an itinerary or route that lengthened my acclimatization period
  • Getting into the best physical condition possible before my climb
  • Discussing Diamox with my primary care physician and getting a prescription before my trip

This trip may be a once in a lifetime opportunity, and I want to maximize my chances of reaching the top of Africa safely. Diamox isn’t a magic pill; but I’m treating it as just one more tool in my kit to get me closer to my goal.

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