Decorative image

Sodium clodronate (Bonefos, Clasteon, Loron)

Sodium clodronate is a type of bisphosphonate. You might have it as a treatment for a number of cancers that affect the bones such as myeloma and secondary breast cancer.

You may have sodium clodronate for 1 of the following reasons:

  • to treat high blood calcium (hypercalcaemia)
  • to strengthen weak areas of bone (osteolytic lesions)
  • to reduce bone pain due to cancers that have spread to the bone
  • to maintain calcium levels in the body after having treatment with another bisphosphonate drug

How sodium clodronate works

Cancer that spreads to the bones encourages the breakdown of bone. This weakens the bones, making fractures more likely. It can also cause pain and releases calcium from the bone cells into the blood. Sodium clodronate helps to slow down the breakdown of bone by the cancer cells.

How you have sodium clodronate

You usually have sodium clodronate as capsules that you take once a day, with water. You take the capsules in the morning, on an empty stomach. You should wait at least 1 hour after you take them before you have a meal or other medicines.

Other foods, especially milk, can stop sodium clodronate being absorbed if they are taken closely together. 

Taking your capsules

You must take tablets and capsules according to the instructions your doctor or pharmacist gives you.

Whether you have a full or empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, not more or less.

Talk to your specialist or advice line before you stop taking a cancer drug.

When you have sodium clodronate

You usually take sodium clodronate every day. For how long you take them depends on your individual needs. 

Tests

You have blood tests before starting treatment and during your treatment. They check your blood calcium levels. You might also need to do urine samples for testing and have tests to check how well your heart and kidneys are working.

Side effects

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

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 or nurse 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.

Common side effects

Each of these effects happens in more than 1 in 10 people (10%). You might have one or more of them. They include: 

Diarrhoea

Contact your advice line if you have diarrhoea, such as if you've had 4 or more loose watery poos (stools) in 24 hours. Or if you can't drink to replace the lost fluid. Or if it carries on for more than 3 days.

Your doctor may give you anti diarrhoea medicine to take home with you after treatment. Eat less fibre, avoid raw fruits, fruit juice, cereals and vegetables, and drink plenty to replace the fluid lost.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treating it once it has started.

This is usually due to the capsules irritating your stomach. Dividing the dose and taking half in the morning and half in the evening may help reduce sickness.

Low levels of calcium in the blood

Low calcium levels in the blood can cause painful muscle spasms, cramps or muscle twitching. You might also get numbness or tingling in your feet, hands or around your mouth.

Liver changes

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes. You have regular blood tests to check for any changes in the way your liver is working.

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:

  • breathing problems especially if you have asthma
  • damage to the jaw bone (osteonecrosis) that can happen if you take sodium clodronate for a long period of time
  • skin problems such as redness, peeling and itching
  • a fracture of the thigh bone that can cause sudden sharp pain in the hip, groin or thigh
  • bone, joint or muscle pain that can be severe

Coping with side effects

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

Important information

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.

It is important that you drink plenty of fluids while having sodium clodronate treatment so that you don't get dehydrated. 

Loss of fertility 

You may not be able to become pregnant or father a child after treatment with this drug. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.    

Pregnancy and contraception

This treatment might harm a baby developing in the womb. It is important not to become pregnant or father a child while you're having treatment and for a few months afterwards. Talk to your doctor or nurse about effective contraception before starting treatment.

Breastfeeding

Don’t breastfeed during this treatment because the drug may come through into your breast milk.

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.

Last reviewed: 
03 Oct 2018
  • Electronic Medicines Compendium
    Accessed August 2018

  • Early breast cancer (preventing recurrence and improving survival): adjuvant bisphosphonates
    The National Institute for Health and Care Excellence (NICE), 2017

  • Myeloma: diagnosis and management
    The National Institute for Health and Care Excellence (NICE), 2016

Information and help