Zoledronic acid (Zometa)

Zoledronic acid is a type of drug known as a bisphosphonate. It has the brand name Zometa.

It reduces the risk of fractures in cancers that affect the bones, such as:  

  • myeloma
  • secondary breast cancer
  • secondary prostate cancer

It also lowers high levels of calcium in the blood (hypercalcaemia), which can happen in secondary bone cancer. 

How it works

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

How you have it

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. 

Drugs into your bloodstream

You have the treatment through a drip into your arm or hand. A nurse puts a small tube (a cannula) into one of your veins and connects the drip to it.

You might need a central line. This is a long plastic tube that gives the drugs into a large vein, either in your chest or through a vein in your arm. It stays in while you’re having treatment, which may be for a few months.

When you have it

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 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.

Side effects

How often and how severe the side effects are can vary from person to person. They also depend on what other treatment you are having. For example, your side effects could be worse if you are also having other drugs or radiotherapy.

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

This effect happens in more than 1 in 10 people (10%). 

Low phosphate levels in the blood 

You will have regular blood tests to check for this. 

Occasional side effects

Each of these effects happens in more than 1 in 100 people (1%). You might have one or more of them. They include:

  • changes to how well your kidney works- you have blood tests to monitor changes
  • low calcium levels in the blood
  • headache
  • flu like symptoms
  • bone pain
  • eye problems
  • low red blood cell levels (anaemia)
  • feeling or being sick
  • loss of appetite

Rare side effects

Each of these effects happens in fewer than 1 in 100 people (1%). You might have one or more of them. They include:

  • irregular heart beat
  • allergic reaction
  • blood pressure changes
  • increased risk of getting an infection
  • bruising, bleeding gums, or nosebleeds
  • difficulty breathing and wheezing
  • skin rash
  • difficulty sleeping (insomnia)
  • dizziness or tremors
  • sore mouth
  • dry mouth
  • diarrhoea
  • constipation
  • stomach pain

Jaw problems

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 father a child while you are 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 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

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment if you need treatment for anything else, including teeth problems.

More information about this treatment

For further information about this treatment go to the electronic Medicines Compendium (eMC) website.

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

This page is due for review. We will update this as soon as possible. 

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