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Sodium clodronate

Clasteon, Loron 520

Do not eat food or have drinks containing milk during the two hours before you take a dose of sodium clodronate, or for one hour after taking a dose.

Do not let yourself become dehydrated - drink several large glassfuls of water each day.

If you buy any medicines or health remedies, you should ask a pharmacist to advise you. Some mineral preparations and antacid medicines will prevent sodium clodronate from working properly.

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About sodium clodronate

Type of medicine


Used for

Bone pain in cancer; and to reduce high blood levels of calcium caused by cancer

Also called

Clodronate disodium (in US); Clasteon®; Loron 520®

Available as

Tablets and capsules

Sodium clodronate is a bisphosphonate and is prescribed for problems which affect bones. It is prescribed to ease bone pain in people with cancer that has spread into the bone, and also to reduce hypercalcaemia associated with some cancers.

In some cancers there can be an excessive breakdown of bone. As this happens, calcium is lost from the bone and seeps into the blood, leading to higher than normal levels of calcium in the blood. This is called hypercalcaemia. Sodium clodronate binds to bone and reduces the rate at which it is broken down. This helps to strengthen bones and prevents the loss of calcium. This in turn reduces the high levels of calcium in the blood.

Before taking sodium clodronate

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking sodium clodronate it is important that your doctor knows:

  • If you are pregnant or breastfeeding.

  • If you have recently had any inflammation of your digestive system such as an upset stomach or bowel.

  • If you are due to have any dental treatment in the near future, or if you have not recently had a dental check-up.

  • If you have any problems with the way your kidneys work.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

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How to take sodium clodronate

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about sodium clodronate and will provide you with a full list of the side-effects which you may experience from taking it.

  • Take sodium clodronate tablets/capsules exactly as your doctor tells you to. It is usual to be prescribed one or two doses to take each day. If you are prescribed one dose to take each day, take it first thing in the morning an hour before you have breakfast. If you are prescribed two doses a day, take your first dose an hour before breakfast and then take your second dose between meals (but see also the following advice).

  • Some foods and other medicines can interfere with how your body absorbs sodium clodronate and this will prevent the medicine from working as it should. Do not eat anything during the two hours before you take a dose, and also for one hour after taking a dose. It is particularly important that you avoid milk (including any drinks which contain milk) during this three-hour period. If you take other medicines, see the advice in the section below.

  • Try to take your doses of sodium clodronate at the same times of day each day. This will get you into a good daily routine and will help you avoid missing any doses.

  • If you do forget to take a dose, just take your next tablet/capsule at the usual time and continue as before. Do not take two doses together to make up for a missed dose.

Getting the most from your treatment

  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. You will need to have regular blood tests during treatment.

  • It is important that you do not become dehydrated during treatment with sodium clodronate. Your doctor will likely advise you to drink several large glassfuls of water each day. This is especially important in warm weather.

  • If you are taking any other medicines, do not take them during the two hours before you take sodium clodronate and wait for at least an hour afterwards before you take your other medicines. If you buy any medicines 'over the counter', check with a pharmacist that they are suitable for you to take. This is because mineral supplements, iron preparations, and some indigestion remedies reduce the amount of sodium clodronate which your body absorbs and this will make your treatment less effective. Also, some painkillers called non-steroidal anti-inflammatory drugs (NSAIDs), can cause kidney problems when taken alongside sodium clodronate.

  • Good dental hygiene is particularly important while you are taking sodium clodronate - brush your teeth regularly and remember to have routine dental check-ups. Also, tell your dentist that you are taking sodium clodronate, as some dental treatments may not be recommended for you.

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Can sodium clodronate cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with sodium clodronate. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.


sodium clodronate side-effects (these affect fewer than 1 in 10 people)

What can I do if I experience this?

Feeling sick (nausea) or being sick (vomiting)

Stick to simple foods - avoid rich or spicy meals. If this becomes troublesome, speak with your doctor


Drink plenty of water to replace any lost fluids. If this becomes troublesome, speak with your doctor

Changes to some blood test results

Your doctor will monitor for these

Less common, but possibly serious side-effects

What should I do if I experience this?

Pain in your thigh, hip, or groin

Speak with your doctor as soon as possible - these can be signs of a thighbone fracture

A loose tooth, or jaw pain with swelling or numbness

Speak with your doctor as soon as possible - these can be signs of a problem called osteonecrosis of the jaw

Ear pain, discharge from an ear, ear infection

These could be signs of a problem called osteonecrosis of the ear. Speak with your doctor straightaway

If you experience any other symptoms which you think may be due to the medicine, speak with your doctor or pharmacist for further advice.

How to store sodium clodronate

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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