We carry bottled oxygen on all of our climbs as a precaution and additional safety measure. The oxygen canister is for use only in emergency situations. It is NOT used to assist clients who have not adequately acclimatized on their own to climb higher. The most immediate treatment for moderate and serious altitude sickness is descent. With Kilimanjaro's routes, it is always possible to descend, and descend quickly. Therefore, oxygen is used strictly to treat a stricken climber, when necessary, in conjunction with descent, to treat those with moderate and severe altitude sickness.
We are aware that some operators market the use of supplementary personal oxygen systems as a means to eliminate the symptoms of AMS. To administer oxygen in this manner and for this purpose is dangerous because it is a temporary treatment of altitude sickness. Upon the cessation of the use of oxygen, the client will be at an even higher altitude without proper acclimatization.
99% of the companies on Kilimanjaro do NOT offer supplementary oxygen - because it is potentially dangerous, wholly unnecessary and against the spirit of climbing Kilimanjaro. The challenge of the mountain lies within the fact that the summit is at a high elevation, where climbers must adapt to lower oxygen levels at altitude. Using supplementary oxygen is akin to putting the mountain at sea level, where nearly everyone can summit.