All of the comments below were valid at our time of travel. Exodus provide comprehensive details at the time of booking but also consult your own doctor before leaving or visit the Travel Doctor website.
Jabs Before travelling you need to take or ensure you have the essential vaccinations - hepatitis A, polio, tetanus, typhoid, meningitis and yellow fever (vaccination certificate needs to be shown on arrival).
Altitude Sickness This can be fatal if you fail to heed the symptoms ( nausea, headaches, vomiting ). The only cure is to descend ... and if you are part of a group this almost inevitably means the end of that part of your trip. For this reason choice of route is very important - the more days you allow to reach the summit the better your chance of success. As you reach higher altitudes good guides ensure you do additional climbing before your evening meal and going to sleep - "climb high, sleep low". Having said this, we climbed to nearly 5,900 metres without any difficulty - it seems more likely to affect the young than the old!!
Other medication You will need to take something like Malarone tablets before, during and after your trip to protect against malaria. It is also worth taking a good supply of Imodium to counteract diarrhoea. Your doctor will advise on any further antibiotics together with something like Diamox to cope with high altitude.