Millions of terminally-ill people around the world die in agony each year, according to doctors.
Few in the developing world have access to pain relief
This is because many, particularly those living in developing countries, do not have access to painkillers.
In some parts of the world, patients with cancer and other terminal diseases are forced to turn to paracetamol, if it is available, to try to relieve their pain.
Few have access to morphine or similar strong drugs administered routinely to patients in the West.
'Die in pain'
"Patients will endure pain," says Dr Twalib Ngoma, executive director of one of Africa's main cancer centres, the Ocean Road Cancer Institute in Dar Es Salaam, Tanzania.
"They die in pain. It is a very, very emotional and disturbing experience for the patient and their relatives."
Medical care for terminally-ill patients has improved in Tanzania in recent years - morphine arrived three years ago.
However, even now patients are not guaranteed this powerful painkiller. "We did not have morphine until the year 2000 but even now morphine availability is not yet assured," says Dr Ngoma.
The situation in Tanzania and most other developing countries contrasts starkly with that in the West.
"If you look at drugs available in developed countries for pain control, you can control more than 90% of patients' pain," says Dr Ngoma.
A survey carried out by the Ocean Road Cancer Institute and the World Health Organization found that access to painkillers was the top priority of terminally ill patients in Tanzania.
"They want to be able to have medication when they need it for pain and other symptoms. It is the most important thing for most patients in Tanzania," says Dr Ngoma.
With limited access to strong painkillers, most people in developing countries associate terminal illness like cancer with excruciating pain.
"In most developing countries because of a lack of drugs, pain is associated with cancer," says Dr Ngoma.
"Patients are afraid that when they have cancer, when it is advanced they will have terrible pain and will die in a lot of discomfort and that is actually what is happening."
Dr Ngoma and others in Tanzania are working to improve the medical care provided to patients who are terminally ill. However, with a lot of other important issues on the agenda the government has yet to make palliative care a priority.
"Palliative care is not yet a priority policy in Tanzania," says Dr Ngoma. "Palliative care is in its infancy in Tanzania. We are just beginning to introduce palliative care to patients."
But he adds: "Most Tanzanians who need palliative care don't get it."
This story is featured in the radio programme Health Matters on the BBC World Service.
here for listening times