Zoledronic acid

Zoledronic acid is a type of drug known as a bisphosphonate Open a glossary item. It is also called Zometa.

You might have zoledronic acid to:

  • prevent problems with the bones such as breaks in the bones (fractures) in myeloma and cancers that have spread to the bone (advanced cancers)
  • lower the chance of breast cancer coming back after surgery in certain situations
  • prevent bone loss for people having aromatase inhibitors Open a glossary item
  • lower high levels of calcium in the blood (hypercalcaemia Open a glossary item), which can happen in secondary bone cancer 

How does zoledronic acid work?

Zoledronic acid attaches itself to bone cells and slows down the rate of bone change. 

How you have zoledronic acid?

Zoledronic acid is a clear liquid. You have it as a drip into your bloodstream (intravenously). 

The drip usually lasts about 15 minutes, but you might have it over a longer period. 

You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

  • central line Open a glossary item
  • PICC line Open a glossary item
  • portacath Open a glossary item

Or you might have it through a small tube put into a vein in your arm each time you have treatment. This is called a cannula.

When do you have zoledronic acid?

Exactly how you have zoledronic acid depends on your circumstances.

Treatment to prevent bone damage

You have zoledronic acid every 3 to 4 weeks. You might need to take calcium and vitamin D supplements if you are having it regularly. 

Treatment to prevent breast cancer coming back

You have zoledronic acid every 6 months for 3 to 5 years.

Treatment to reduce calcium levels

You have it as a single treatment to reduce the calcium levels in your blood. 


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

You see the dentist for a check up before starting zoledronic acid.

Side effects

Side effects can vary from person to person. They also depend on what other treatment you are having. 

When to contact your team

Your doctor, nurse, or pharmacist will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects 

  • your side effects aren’t getting any better

  • your side effects are getting worse

Early treatment can help manage side effects better.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

Common side effect

It’s common to get low phosphate levels in the blood with zoledronic acid. This side effect can happen in more than 10 in 100 people (more than 10%). You will have regular blood tests to check for this. 

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

  • changes to how well your kidney works- you have blood tests to monitor changes.it is important to drink planty of fluids before and after your treatment.
  • low calcium levels in the blood– you have regular blood tests to check on this. You have calcium and vitamin D supplements to take. You must take them as the doctor or nurse tells you to.
  • headache
  • flu like symptoms– most likely to happen in the first 3 days after treatment. You can take paracetamol if it does.
  • pain in different parts of your body such as your bones, muscles and joints
  • general aches
  • low red blood cell levels (anaemia)
  • feeling or being sick
  • loss of appetite
  • high temperature
  • red eyes (conjunctivitis) or sore eyes

Rare side effects

These side effects happen in fewer than 1 in 100 people (less than 1%). You might have one or more of them. They include:

  • changes to your heartbeat
  • allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness - some allergic reactions can be life threatening, alert your nurse or doctor if notice any of these symptoms
  • blood pressure changes either low or high
  • increased risk of getting an infection due to low levels of white blood cells in the blood
  • bruising, bleeding gums, or nosebleeds due to low levels of platelets in the blood
  • difficulty breathing and wheezing
  • cough
  • skin problems such as a rash, itchy skin or hives
  • sleep disturbances and sleepiness
  • dizziness
  • sore or dry mouth
  • diarrhoea or constipation
  • nerve changes causing either increased sensitivity, numbness, tingling (pins and needles) or prickling
  • stomach pain
  • tremors
  • anxiety
  • eye problems such as blurred vision or inflammation
  • increased sweating
  • muscle cramps
  • blood and protein in the urine
  • pain, swelling, irritation, hardening or redness at the injection site
  • chest pain
  • weight gain
  • low amounts of magnesium and potassium in the blood – you have regular blood tests to check on this
  • changes to taste
  • indigestion
  • feeling weak and lacking in energy
  • swelling of feet and hands

Damage to the bones

Damage to the bones (for example in the jaw or thigh) is a rare but serious side effect. Contact your medical team if you have any of the following:

  • ear pain
  • discharge from your ear
  • an ear infection
  • pain in the mouth, teeth or jaw
  • loosening of a tooth
  • pain or weakness in your hip, thigh or groin

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

Other medicines, foods and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.

Pregnancy and contraception

It is unknown whether treatment may or may not harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you are having treatment. Let your team know straight away if you or your partner become pregnant while having treatment.

Talk to your doctor or nurse about effective contraception you can use during treatment. Ask how long you should use it before starting treatment and after treatment has finished.


It is not known whether this treatment affects fertility Open a glossary item in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.


It is not known whether this drug comes through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.

Treatment for other conditions

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

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