If you are planning to climb Mount Kilimanjaro you will sooner or later hear about altitude sickness.For those unfamiliar with the ins and outs of altitude illness, here are answers to the most common questions regarding mountain sickness.

The definition of altitude

High Altitude: 1500 – 3500 m (5000 – 11500 ft)
Very High Altitude: 3500 – 5500 m (11500 – 18000 ft)
Extreme Altitude: above 5500 m (18000 ft)

What is altitude sickness?
Altitude sickness is a range of symptoms that can occur when someone ascends to a high altitude too rapidly, without sufficient acclimatization.
The body can adjust to the reduced air pressure at higher altitude, but only at a rate of about 300 m (1000 ft) altitude gain per day.
If you ascend faster, and everybody climbing Kilimanjaro will, then you may develop altitude sickness.

There are three main forms of altitude sickness:
AMS (Acute Mountain Sickness) is very common when climbing Kilimanjaro.
HAPE (High Altitude Pulmonary Edema) is a fluid build up in the lungs.
HACE (High Altitude Cerebral Edema) is fluid build up in the brain.
Both HAPE and HACE are potentially fatal but are thankfully extremely rare during a well planned Kilimanjaro climb.
What exactly causes the individual symptoms of altitude sickness is still not fully understood. If you want to know more details, there is a link to an excellent tutorial at the bottom of this page.

There is also a range of other symptoms you are likely to experience during a Kilimanjaro climb due to the altitude. They are considered normal and shouldn’t worry you:

You breathe faster,
you are out of breath sooner,
you may experience periodic breathing at night (where you stop breathing for up to 15 seconds, and then breathe very fast to make up for it, scary but harmless),
you may wake up frequently at night,
You need to urinate a lot more often.
None of those symptoms are altitude sickness.

What are the symptoms of altitude sickness?

The symptoms of AMS are headaches, loss of appetite, nausea, vomiting, sleeplessness, fatigue, dizziness. Everybody can expect to experience at least some of these symptoms in a mild form.
The most obvious symptoms for HAPE are extreme breathlessness, even at rest; rattling breath, coughing with pink froth and blue lips or finger nails.
HACE becomes apparent as a lack of coordination, inability to walk in a straight line, confusion and irrational behaviors (to the point of not acknowledging the symptoms).

How dangerous is altitude sickness?

The symptoms of acute mountain sickness as described above are self limiting and not dangerous. In fact, your guides may tell you during the briefing not to worry, that it is totally normal to be throwing up repeatedly during that last final push top the summit. Nice…
However, if you do experience symptoms, your guides should also keep monitoring you, because AMS can progress to one of the more severe forms of altitude sickness.

HAPE and HACE are potentially fatal!
Make sure that you always remain in contact with your guides and let them know exactly how you are feeling. Also keep an eye on your climbing partners, since people suffering from these severe conditions may not be able to correctly assess their own condition.
Anybody experiencing symptoms that could indicate HAPE or HACE needs to descend IMMEDIATELY or they will die.
But please don’t panic now. As I said above, these conditions are extremely rare, provided you act sensibly when on the mountain.

Who gets altitude sickness?

Anybody can get altitude sickness. There is no way to predict how your body will react if exposed to high altitude without proper acclimatization.
Susceptibility to altitude sickness is random. Fitness is no protection. People who are extremely fit and exercise a lot get it just an easily as couch potatoes. There are many stories that indicate they may be even more susceptible!
Men appear to be more susceptible than women, especially young and fit men. (Competitiveness and the desire to show off plays a part in this. Men will often ascend faster. Too fast.)
Older people seem to be less susceptible. (Older people will ascend more slowly, and nothing protects you better from altitude sickness than ascending slowly.)

When do you get altitude sickness?

Highly susceptible people can experience symptoms from 2500 m (7000 ft) onwards, in rare cases even below that. The chance of developing AMS increases with the height but the rate of altitude gain is even more important.
Mt. Kilimanjaro is 5895 m (19340 ft) high. Pretty much everybody on a Kilimanjaro climb will experience some symptoms of altitude sickness during that last push to the summit.
There are other factors that increase the likelihood of altitude sickness, apart from the absolute height itself:
Rate at which a height is achieved (the faster you ascend the bigger the risk of developing symptoms, this factor is more important than the absolute height itself!)
Time spent at height (symptoms start appearing within 6-10 hours though they can be delayed)
Physical exertion
Dehydration

Symptoms of acute mountain sickness typically take one or two days to disappear. If you keep ascending they may not go away. For most people the symptoms come and go during the day, disappear overnight, only to come back the next day as the climb continues.
AMS can be very unpleasant, but with the right preparation and at a sensible pace, most people can climb to at least the last camp below the crater rim (around 5700m). It’s that last push to the summit where AMS becomes the make it or break it issue.

You climb Kilimanjaro with knowledge that every detail of your trip has been designed by one of the professional mountain guide and high altitude experts.
Our first goal
Your safety is our paramount concern on your Kilimanjaro trek. You leave home with the comfort of knowing that during your trek all you have to worry about is putting one foot in front of the other. We take care of the rest.

Twice a day our guides perform a through health check, using their specialized High Altitude Medical Paper and conjunction with pulse-ox meters. Regular medical checks help keep your motivation and our guides can determine your condition.