8-Day Kilimanjaro Rongai Route Trek to Uhuru Peak via Marangu

Altitude Sickness

The science behind altitude sickness is fairly simple to understand. Throughout the troposphere (that is, from sea level to an altitude of approximately 10 km), the air composition remains the same: about 20% oxygen and nearly 80% nitrogen.

So when you read that there is a lack of oxygen at the summit, that is not strictly true - oxygen still makes up 20% of the air. The real issue is not a lack of oxygen, but lower air pressure.

To put it more precisely, atmospheric pressure drops by about one-tenth for every 1000 m of altitude. Thus, the air pressure at the top of Kilimanjaro is approximately 40% of that found at sea level.

In layman's terms, although each breath at the summit is still 20% oxygen, just as it is at sea level, it becomes much harder to fill your lungs because the atmosphere is not pushing as much air into them.

Acute Mountain Sickness (AMS)

Acute Mountain Sickness (AMS) - also known as altitude sickness or altitude illness - is a pathological effect on humans caused by ascending to high altitudes too quickly, where lower oxygen availability inhibits normal physiological processes.

People typically begin experiencing Acute Mountain Sickness symptoms at about 10,000 feet (3,000 m).

Some people can experience symptoms as low as 8,000 feet (just over 2,400 m).

Due to Kilimanjaro's rather rapid ascent profile, altitude sickness among trekkers is unfortunately quite common.

The following are symptoms of Acute Mountain Sickness:

• Fatigue
• Headaches
• Nausea and dizziness
• Shortness of breath
• Disturbed sleep
• Loss of appetite
• Very bad headaches that are not relieved with medication

Shortness of Breath

If you suffer any of the symptoms above, it is important to communicate to your climbing partners and guide how you are feeling.

These symptoms generally disappear if you rest for a day at the altitude where they first began. This is why an acclimatization day, where you climb high and sleep low, is so important.

Golden Rules

Trekking Kilimanjaro need not be a very risky or dangerous adventure as long as you follow some basic rules.

If you have a chance to pre-acclimatize before trekking Mount Kilimanjaro, do so. A good option in Tanzania is to trek the neighboring Mount Meru (4,565 m) before attempting Kilimanjaro.

1. If you are a novice high-altitude trekker, then choose a route itinerary that is at least seven days long (6 up, 1 down). In our opinion, the seven-day Machame or 7/8-day Lemosho are the most suitable routes for the average trekker.
2. Ensure the route allows for a good climb-high, sleep-low opportunity (both the Machame and Lemosho do).
3. When on the mountain, make a point of going as slowly as possible. Do not overexert yourself, even on the lower reaches.
4. Drink plenty of fluids (2.5-4 liters a day).
5. Do not drink alcohol, take stimulants, smoke, or consume caffeine on the mountain.
6. We recommend taking acetazolamide (Diamox).

Finally, as recommended by the charity Altitude.org, always remember these 3 golden rules when at altitude:

• If you feel unwell, you have altitude sickness until proven otherwise.
• Do not ascend further if you have symptoms of altitude sickness.
• If you are getting worse, then descend immediately.

Preventative Medications - Diamox

Acetazolamide, or Diamox, is a drug that has been proven effective in mitigating altitude sickness.

The drug helps increase the acidity of the blood by acting as a diuretic and promoting urination.

Increased acidity in the blood is interpreted by our bodies as increased CO2, and so you begin breathing deeper and faster to get rid of the CO2. Deeper, faster breathing increases the amount of oxygen received by the blood and helps prevent the onset of AMS symptoms.

It is important to note that Diamox is a prophylactic (preventative medicine) and does not cure the symptoms of AMS.

Once altitude sickness symptoms have started, the only way to stop them is descent. Under no circumstances should Diamox be used to continue an ascent with AMS.

Diamox is also a prescription drug, so it is important that you first consult your doctor to check whether it is suitable given your particular medical history.

It is not suitable for pregnant women or anyone with kidney or liver disease issues.

We recommend taking Diamox for 2-3 days, 2 weeks before departure, to test whether you experience any side effects.

Typical Side Effects Associated with Diamox

• Frequent urination

- Everyone experiences this when taking Diamox. It can result in the development of kidney stones, so it is important that you drink plenty of fluids while taking the medication.

• Numbness and tingling in the fingers, toes, and face

- Many people experience this side effect when taking Diamox. The sensation is a little discomforting but not dangerous.

• Taste alterations (some foods might taste strange)
• Nausea, vomiting, and diarrhea

- This is rare. These side effects should be identified during your test before departing for Kilimanjaro. Unfortunately, these side effects are common with AMS and therefore can easily be misdiagnosed as AMS.

• Drowsiness and confusion are also possible - again, these side effects can be confused with AMS.

Diamox comes in 250 mg tablets. Most people take half a tablet in the morning and half in the evening.

You should start taking the tablets one day before arriving in Kilimanjaro and continue with the same dosage for all ascent days. You can stop taking Diamox on descent.