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How to avoid Acute Mountain Sickness.

1. How to avoid Acute Mountain Sickness.

Acute Mountain Sickness or Altitude Mountain Sickness.

Acute Mountain Sickness (AMS), hypobaropathy and soroche, is an illness caused by exposure to the low air pressure, especially low partial pressure of oxygen, which many climbers experience at high altitudes. Acute mountain sickness is caused by exerting yourself at high altitudes elevation, especially if you have not been properly acclimatised. It is most common at altitudes above 2400 metres. Kilimanjaro’s peak is nearly 6000 metres above sea level. At this height, the air pressure (and the amount of oxygen it contains) is less than half that at sea level, and has been said to be comparable to ‘working with only one lung’. AMS can be serious, especially as it can be debilitating, and it generally occurs far from places where medical treatment can be easily administered.

Not everyone suffers from AMS, of course, and it is very difficult to predict who is or is not vulnerable to it. Generally speaking, a fit person is less vulnerable than an unfit person, because their cardiovascular system can operate at low pressures longer without as much strain. Even so, anyone can be vulnerable at altitudes above 3500 metres, no matter their fitness level, if they have not spent some time getting used to the low atmospheric pressures first. Undoubtedly the best way to see how you are going to react to high altitude is to go high and try to do some exercises. For most of us that isn’t an option so a good alternative is to have a session with a specialist altitude training programmer  that have equipment that simulates the effects of altitude.

How to avoid Altitude Sickeness

Altitude sickness, also called Acute Mountain Sickness (AMS), is an illness caused by exposure to the low air pressure; especially low partial pressure of oxygen, which many climbers experience at high altitudes. There are a number of practical steps that you can take to minimize the chances of having to abandon your climb of Kilimanjaro due to the effects of altitude sickness.

Acclimatize prior to the climb.

Easier said than done if you live at sea level but if you are able to spend time at high altitude prior to the actual Kilimanjaro climb then this is the very best way to avoid altitude sickness. Climbing Mount Meru prior to Kilimanjaro is also an excellent option.

Start the climb in the best possible health and with an excellent level of physical fitness. If you are fatigued, unwell or stressed you are more likely to suffer from altitude sickness.

Walking slow and steady.

You need to keep your respiration rate low enough to maintain a normal conversation. If you are panting or breathing hard, you must slow down. Overworking your heart and lungs substantially increases your chance of becoming ill.

Drink much more water each day.

Getting up in the middle of the cold night may be an unpleasant thought but altitude dehydrates you and better you hydrate the quicker your body is able to acclimatize.

Proper hydration helps acclimatisation dramatically. You need to drink at least three litres each day. As dehydration presents many of the same symptoms as altitude sickness, your chances of being allowed to continue are best if you stay hydrated.

Eat well.

One very common effect of the altitude is a reduced appetite. We offer enticing meals, rich in “good” carbohydrates, carbohydrate foods is the most efficient fuel for optimizing performance at high altitude elevation, speeding up recovery and replenishing muscle glycogen stores for the next day’s activity. A high carbohydrate diet at altitude is recommended as an intervention to alleviate symptoms of AMS (acute mountain sickness)” as it increases ventilation and blood oxygenation. You should eat as much as you can at every meal. This will give you plenty of energy and help you to feel great during climb Kilimanjaro. It keeps warm and sleep well at night.

Walk high, Sleep well.

It is best to gradually climb higher each day, then descend lower to sleep. This lets you gradually become accustomed to lower pressures, and then recover somewhat overnight.

Sleeping well in a tent is a acquired skill. Spend a few nights out in your tent and sleeping bag prior to your climb so that you have your routine nailed and are used to sleeping in a sleeping bag on a hard surface.


Diamox is the prescription name for the generic drug acetazolamide, and though acetazolamide is prescribed for the medical treatment of glaucoma, sleep apnea, epilepsy and hypertension, it’s also used to prevent altitude sickness. The general consensus of the research is that Diamox is helpful in avoiding Acute mountain sickness. We use it when climbing Kilimanjaro. We recommend you to use diamox when you climb and its effects yourself, it is a prescription drug. You should consult with your doctor before taking it.


Relax and think positive. Although not pleasant the vast majority of people suffer only mild altitude sickness. Don’t think that every headache is cerebral oedema and every cough pulmonary oedema as this is unlikely. By relaxing and enjoying the climb you are far more likely to have a trouble free experience.

Choose the right route for your Kilimanjaro climb.

Most people book their Kilimanjaro climb well ahead, and this is where you can make the first mistake.

There are several climb routes up Kilimanjaro and there is a huge number of operators. A Kilimanjaro climb is expensive, so it’s tempting to look for the cheapest deal.

The cheapest Kilimanjaro climbs are also the shortest. Every day on the mountain will add a few hundred dollars to the price. It is possible to book a five day or even four day climb, and it would be a mistake to do so.

No responsible operator should be offering four day climbs to people who have no previous experience at high altitude trekking and are not acclimatised.

The (admittedly highly unreliable) statistics from the registration books at Mount Kilimanjaro National Park indicate that of all climbers on five day routes, only little over a quarter reach the summit!

All the five day routes offer an opportunity to add an extra day for acclimatization. Do spend the money on that extra day!

If you want to increase your chances of reaching the summit further, consider choosing one of the longer routes.

2. Learn how to recognize the effects and symptoms of altitude sickness

Altitude sickness and the effects of altitude on your body are a reality and need to be understood. We will try and describe in layman’s terms the basics of altitude sickness, the symptoms, how to treat it and the safety precautions involved when you climb Kilimanjaro. Though the dangers of altitude and the effect altitude has on your body while climbing Kilimanjaro is a reality, do not get discouraged from following your dream to climb Kilimanjaro. It needs to be illustrated to understand and prepare for successful Mount Kilimanjaro summit attempt.

What happens to your body when you climb Mount Kilimanjaro

If you remember the basics of biology and anatomy, human blood consists of red blood cells. The primary role of red blood cells amongst other things is to transport oxygen around your body. Now as you climb Kilimanjaro and slowly gain height, the effects of altitude on your body are going to become more apparent. The thinner air results in less oxygen. Air at sea level comprises about 21% oxygen, while the barometric pressure averages about 1 bar (1000 mbar). As altitude increases, the oxygen concentration remains the same but since the pressure falls the number of oxygen molecules per breath is reduced. At 3,500 meters the barometric pressure is only about 630 mbar (depending on weather conditions), so there are roughly 40% fewer oxygen molecules per breath. In order then to supply adequate amounts of oxygen to your body your breathing rate – even while resting –  must increase.

Without you even being conscious of the process, your body which likes to keep the balance, recognizes the fact that the oxygen levels are dropping. A secret code that gets sent from the brain gets sent to your neural network initiating your blood-making mechanism to produce more red blood cells. The reason is the current numbers of red blood cells are not sufficient, so your body creates a lot more to increase its chances of getting more oxygen. This process has some apparent side effects.

This extra breathing increases the amount of oxygen in the blood, but not to sea level volumes. Since the amount of oxygen required for activity is the same, the body must adjust itself to coping with less oxygen. This process is known as acclimatization. Failure to give your body the opportunity to undergo this process may lead to a condition known as acute mountain sickness or AMS.

Mount Kilimanjaro altitude sickness is classified as entry into the extremely high altitude zone:

1.High – 2,500 – 3,500 meters

2.Very High – 3,500 – 5,500 meters

3.Extremely high – 5,500+ meters.

AMS – Acute Mountain Sickness

Acute mountain sickness is common at altitude elevations over 3,000m is common and normal for most people to experience. During the regular acclimatization succession many climbers encounter the mild altitude symptoms and should be considered normal and acceptable. Altitude sickness is dependent upon several reasons; elevation gained with the rate of ascent, and the individual’s susceptibility level.

Mild altitude sickness does not interfere with regular activity, and symptoms generally subside within 2-4 days as the body acclimatizes. Symptoms usually start 12-24 hours during the altitude gain and begin to decrease in sternness about the third day, and they tend to be especially bad at night when respiratory drive is reduced. The mild AMS signs are a headache, dizziness, fatigue, shortness of breath, loss of appetite, nausea, disturbed sleep, and a general feeling of malaise. As long as symptoms are mild, and only a nuisance, ascent can continue at a moderate rate.

Altitude sickness is considered to be a neurological problem caused by changes in the central nervous system. It is a very mild form of High Altitude Cerebral Edema. When hiking, it is essential that you communicate any symptoms of altitude sickness immediately to the had guide. The only cure is acclimatization or else descent. Symptoms of mild AMS can be alleviated with Ibuprofen but keep in mind that reducing the symptoms is not curing the problem or treating the cause. If symptoms of mild AMS worsen, the climber may show early signs of moderate acute mountain sickness.

Moderate Acute Mountain Sickness.

These signs includes severe headache, nausea and vomiting, increasing weakness and fatigue, shortness of breath, and decreased coordination (ataxia). At this stage only descent can reverse the problem. Although the victim may still be able to walk on their own but normal activity is difficult. Descending even a hundred meters may help and significant change will be seen with a descent of 300-500 meters at the lower altitude within twenty-four hour. When the symptoms have subsided at this point, the person has become acclimatized to that altitude and can begin ascending again.

Most excellent assessment for moderate AMS is to walk heel to toe in a straight line. Just like a sobriety test, a person with ataxia will be unable to walk straight, apparent this is an indication for immediate descent. It is essential that the person descends before the ataxia reaches the point where they can no longer walk on their own. Our staff are trained in rapid evacuation techniques. The group member will be carried to a location of complete safety within hours, from any point on the mountain.

Severe Acute Mountain Sickness

Acute Mountain Sickness is increase in the severity of the aforementioned symptoms, which requires immediate descent to lower altitude of around 1,000 meters.

  • shortness of breath at rest
  • inability to walk & decreasing in mental status
  • fluid build-up in the lungs​

HAPE and HACE as 2 other severe forms of altitude illness. Both of these happen less frequently, especially to those who are properly acclimatized. When they do occur, it is often because inexperienced people may go too high too fast, or else may go very high and stay there. The lack of oxygen results in leakage of fluid through the capillary walls into either the lungs or the brain.

High Altitude Pulmonary Edema (HAPE)

High Altitude Pulmonary Edema results from fluid build-up in the lungs. The fluid in the lungs prevents effective oxygen exchange. As the condition becomes more severe, the level of oxygen in the bloodstream decreases, and this can lead to cyanosis, impaired cerebral function, and death.

Symptoms include:

  • shortness of breath even at rest & tightness in the chest
  • marked fatigue & weakness
  • feeling of impending suffocation at night
  • persistent cough bringing up white, watery, or frothy fluid

Confusion, and irrational behavior are signs that insufficient oxygen is reaching the brain. In cases of HAPE, immediate descent to around 1000m altitude is a necessary life-saving measure. Anyone suffering from HAPE must be evacuated to a medical facility for proper follow-up treatment.

High Altitude Cerebral Edema (HACE)

High Altitude Pulmonary Edema is the result of swelling of brain tissue from fluid leakage.

Symptoms can include:

  • headache & loss of coordination (ataxia)
  • weakness & decreasing levels of consciousness
  • disorientation & loss of memory
  • hallucinations & psychotic behaviour
  • coma

It generally occurs after a week or more at high altitude. Severe instances can lead to death if not treated quickly. Immediate descent to 1,000m altitude is a necessary life-saving measure. Anyone suffering from HACE must be evacuated to a medical facility for proper follow-up treatment. No specific factors such as age, sex, or physical condition can be used to predict susceptibility to altitude sickness. Some get it, and others don’t.

What is acclimatization and how is it done on Mount Kilimanjaro

Acclimatization is the process your intelligent body goes through to adapt to the effects of altitude on your body while you climb Kilimanjaro. The human body needs time to adapt. When you climb Kilimanjaro, they best way to adapt to the effects of altitude is to go slowly ‘Pole Pole’ in Swahili language. The best way for your body to adapt to altitude is to move really, really slowly. This allows the intelligent body to adapt to the effects of altitude on Kilimanjaro. We also recommend that climbers drink at least 3 – 4 litres of water a day.

There’s no need to rush or exert your self while acclimatising on Mount Kilimanjaro. You shouldn’t climb higher than 300-500 meters/900-1500 ft per day. That’s not very hard to do and you might be tempted to go farther. But all it will bring you is headache, sleeplessness and possibly mountain illness.
​Sometimes we have to push the limits but situations might force us into circumstances that we don’t like. That’s one thing. But to come up with mountain sickness due to impatience and ignorance is sad. It could cost you your life. The most important is rapid descent. Mountain sickness can kill fast!