Bisphosphonates work by reducing the number and action of the osteoclasts in the bones. This slows down the process of bone breakdown while allowing the production of new bone to carry on as normal.
Bisphosphonates can strengthen existing bone and reduce the damage caused by secondary breast cancer in the bone. They can also help to control calcium levels in the blood.
How are bisphosphonates given?
Bisphosphonates can be given as a tablet/capsule (orally) or into a vein (intravenously). Both oral and intravenous treatments are effective and your specialist will recommend whichever is most appropriate for you.
They are usually given for as long as the secondary cancer in the bone is under control.
Oral bisphosphonates are to be taken daily. Ideally they should be taken first thing in the morning on an empty stomach with water only. They can’t be absorbed when there is food or calcium-containing liquid, such as milk, in the stomach.
- Ibandronic acid (Bondronat) is given as tablets. After taking them, it’s important to wait for at least 30 minutes before you eat, drink or take any other medication. You should also stay sitting or standing for one hour after taking them to avoid any irritation to the oesophagus (gullet).
- Disodium clodronate (Bonefos, Loron, Clasteon) can be either a given as a tablet or capsule. There is no need to stay sitting or standing after taking them and, if you wish, you can lie down immediately.
These can be given at your local hospital or hospice. Usually you will need blood tests before the treatment is given. This includes a test to monitor your kidney function (see Side effects of bisphosphonates and denosumab) and to check the levels of calcium in your blood.
- Disodium pamidronate (Aredia) is given over a period of 90 minutes, every three to four weeks.
- Ibandronic acid (Bondronat) is given over a period of 15 to 60 minutes, every three to four weeks.
- Zoledronic acid (Zometa) is given over a period of 15 to 30 minutes, every three to four weeks. Once you’ve had this treatment for around a year you may be able to have it every 12 weeks instead.
Bisphosphonates can cause significant side effects. If you are concerned about any side effects, regardless, talk to your specialist team as they may be able to help you manage them. Read more about the side effects of bisphosphonates and how you can manage them.