There are two different types of cells found in bone – osteoclasts and osteoblasts. Osteoclasts destroy the old bone and osteoblasts deposit new minerals and build new bone. Cancer cells which have spread to the bone produce chemicals that change the activity of these cells, upsetting the normal balance. This commonly causes small holes in the bone due to overactivity of the osteoclasts.

Bisphosphonates are drugs that restrict the action of the osteoclasts (the cells that destroy bone). They are not a treatment for the cancer itself but may help to reduce the breakdown of the bone. This can reduce the risk of fracture, hypercalcaemia and spinal cord compression, and reduce discomfort. Your doctor may recommend that you have treatment with bisphosphonates to treat bone-pain, prevent broken bones and reduce the need for radiotherapy treatment.

Bisphosphonates are also commonly used to treat high blood calcium levels.

Bisphosphonates may be given into a vein through a drip (intravenously) in the outpatient department, every 3–4 weeks. Some bisphosphonates can be taken as tablets, which must be taken on an empty stomach at least half an hour before food. You cannot eat or drink for six hours (usually overnight) before taking some of the tablets and they should be taken when you are sitting or standing, not lying down. Your doctor, nurse or the pharmacist will explain how you should take your tablets. You may also be given calcium tablets as these can help to strengthen bone.