Browser does not support script.
Skip to main content
search here
Macmillan and Cancerbackup merged in 2008. Together we provide free, high quality information for people affected by cancer through our publications, website and phone service. Find out more|.
Find out how we produce our information|
This information is about a drug called zoledronic acid that can be used when cancer has spread to the bones|.
Zoledronic acid belongs to a group of drugs called bisphosphonates|. Bisphosphonates are commonly used to treat bone thinning (osteoporosis).
In certain situations, bisphosphonates can help protect your bones against some of the effects of secondary bone cancer, such as pain| and bone weakness|. Secondary bone cancer occurs when the original (primary) cancer spreads to form a secondary cancer (metastasis) in the bone.
Zoledronic acid is often given alongside other cancer treatments|. As well as being used for some types of secondary bone cancer, it has been shown to be effective for people with myeloma| (a cancer of the plasma cells, which are a type of blood cell). It is also used to lower a raised calcium level in the blood.
In secondary bone cancer, calcium, which helps strengthen the bones, can be lost from the damaged bone and can seep into the bloodstream. A raised level of calcium in the blood is called hypercalcaemia|. It can cause symptoms such as feeling or being sick (nausea or vomiting), tiredness|, irritability and sometimes confusion. Zoledronic acid can help reduce high levels of calcium.
Secondary cancer in the bones may cause them to weaken, and in some situations, they may fracture or break. Zoledronic acid can help re-strengthen the bone and reduce the risk of fractures.
Cancer can affect the bones in different ways, and zoledronic acid is not helpful for all cancers that affect the bones. Your doctor or specialist nurse can tell you if it would be helpful for you.
In normal bone, two types of cells called osteoclasts and osteoblasts work together to shape, rebuild and strengthen existing bone:
Myeloma and some secondary bone cancers can produce chemicals that make the osteoclasts work harder. This means that more bone is destroyed than rebuilt, which leads to weakening of the affected bone. This can cause pain and means that the bone can fracture or break more easily.
Zoledronic acid targets areas of bone where the osteoclast activity is high. It helps bring the balance of osteoclast and osteoblast activity back to normal by reducing the activity of the osteoclasts. This can reduce pain and help strengthen the bone. It also means that less calcium will be lost from the bones.
Zoledronic acid is given by a drip (infusion) into the vein through a fine tube called a cannula. It is usually given in the outpatient department at the hospital. The infusion takes at least 15 minutes and is given once a month.
If you are having zoledronic acid to reduce pain or strengthen your bones, you may need to take it for as long as it seems to be working.
Zoledronic acid to lower calcium levels is usually given as a single 'one-off' dose.
Each person’s reaction to any medication is different. Most people have very few side effects while others may experience more. The side effects described below won't affect everyone having zoledronic acid.
We have outlined the most common side effects but haven't included those that are rare and therefore unlikely to affect you. If you notice any effects that aren't listed below, discuss them with your doctor or nurse.
Sometimes pain in the affected bone can become worse for a short time when you start taking zoledronic acid. If this happens, your doctor can prescribe pain-relieving drugs for you until it wears off.
A high temperature, chills, and muscle and joint pains can sometimes occur. Let your doctor know if these effects are troublesome. It may be helpful to take mild painkillers|.
This is extremely rare and usually only temporary. It is unlikely to cause you any symptoms.
Occasionally, zoledronic acid can affect how the kidneys work. This does not usually cause any symptoms, and the effects are mild. Your doctor will check how well your kidneys are working during your treatment by doing blood tests.
Your doctor can prescribe eye drops to ease this.
Symptoms of anaemia include feeling very tired and breathless. Your doctor can check whether you're anaemic by doing a blood test.
This is not common. It is important to drink plenty of fluids. Let your doctor know if you are getting headaches, and they will advise you about what medicines to take.
If this happens, your doctor can prescribe very effective anti-sickness (anti-emetic) drugs| to prevent or greatly reduce the sickness.
An uncommon side effect of zoledronic acid is a condition called osteonecrosis of the jaw. This is when healthy bone tissue in the jaw becomes damaged and dies. Gum disease, problems with your dentures and some dental treatments, such as having a tooth removed, can increase the risk of this. So before you start taking the drug you'll be advised to have a full dental check-up.
During treatment with bisphosphonates it's very important to look after your teeth by brushing them regularly and having routine dental check-ups. Always let your dentist know that you're taking bisphosphonates. Some of the symptoms of osteonecrosis can include pain, swelling, redness of the gums, loose teeth or a feeling of numbness or heaviness in your jaw. Tell your cancer specialist and dentist straightaway if you have any of these symptoms.
You may be asked to take calcium and vitamin D supplements while having treatment with zoledronic acid. Your doctor will let you know if this is necessary.
This section has been compiled using information from a number of reliable sources, including:
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.