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Samarium-153 EDTMP


Trade/other name(s): Quadramet, samarium-153, Sm-153, samarium-153 lexidronam pentasodium

Why would this drug be used?

This drug is used to help relieve bone pain in some types of cancer that have spread to the bones.

How does this drug work?

Samarium-153 EDTMP is a type of drug known as a radiopharmaceutical. It is made up of a radioactive component (samarium-153) attached to another substance (EDTMP) that is attracted to bones. When it is injected into the blood, it travels to the bones (specifically to areas where the bone content is changing, such as sites of cancer spread). Once there, it gives off small amounts of radiation that travel only a very short distance. The radiation damages the DNA inside the nearby cancer cells, which causes the cells to die.

Before taking this medicine

Tell your doctor…

  • If you are allergic to anything, including medicines, dyes, additives, or foods.
  • If you have any type of kidney disease or congestive heart failure. This drug leaves the body mainly through urine, so you will be given fluids before your treatment to help get it out of the body as soon as possible. People who have kidney disease or congestive heart failure might have trouble taking in extra fluids and might need careful monitoring.
  • If you have trouble controlling your urine. This drug leaves the body mainly through urine. Your doctor may recommend putting a catheter (a thin, flexible tube) into your bladder before treatment to limit the risk of radiation getting on your clothes or bed linens. Most of the excess radiation will leave the body within 12 hours of treatment.
  • If you have any type of abnormal heart rhythm. This drug might affect the rhythm of the heart. Your doctor might need to monitor you more closely during treatment.
  • If you have any other medical conditions such as heart disease, liver disease, diabetes, gout, or infections. Your doctor may need to monitor you more closely during treatment.
  • If you are pregnant or if there is any chance of pregnancy. This drug can cause harm to the fetus if it is given to a woman during pregnancy. Women who could become pregnant need to have a negative pregnancy test before getting this drug. Both women who could become pregnant and their male partners should use effective birth control after treatment. Check with your doctor about what kinds of birth control can be used with this medicine and how long they should be used after treatment. Tell your doctor right away if you think you might be pregnant.
  • If you are breastfeeding. This drug could pass into breast milk, which could affect the baby. Women who are taking this drug and their doctors should decide if they will get this drug or breastfeed, but they should not do both.
  • If you think you might want to have children in the future. This drug might affect fertility. Talk with your doctor about the possible risk with this drug and the options that may preserve your ability to have children.
  • About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs. In fact, keeping a written list of each of these medicines (including the doses of each and when you take them) with you in case of emergency may help prevent complications if you get sick.

Interactions with other drugs

This drug is not known to interact directly with other drugs at this time, but this does not necessarily mean that it will not interact with other drugs. Be sure your doctor knows about all of the drugs and supplements you are taking.

This drug can lower your blood platelet count, which can increase your risk of uncontrolled bleeding (see “Precautions”). If your platelet count becomes low, you might need to avoid other drugs or supplements that interfere with blood clotting, because they could further raise the risk of bleeding. These include:

  • Non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve, Naprosyn) and many others
  • Warfarin (Coumadin), dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis), or other blood thinners, including any type of heparin injections
  • Anti-platelet drugs such as clopidogrel (Plavix) or prasugrel (Effient)
  • Vitamin E

Note that many cold, flu, fever, and headache remedies contain aspirin or ibuprofen. Ask your pharmacist if you aren’t sure what’s in the medicines you take.

Check with your doctor, nurse, or pharmacist about your other medicines, herbs, and supplements, and whether alcohol can cause problems with this medicine.

Interactions with foods

No interactions with foods are known at this time. Check with your doctor, nurse, or pharmacist about whether any foods might be a problem.

Tell all the doctors, dentists, nurses, and pharmacists you visit that you are taking this drug.

How is this drug taken or given?

This drug is given as a single injection into a vein (IV) over about 1 minute. The dose is based on your weight. Because the drug includes radiation, the medical staff will use special precautions while giving it to you.

Before the injection, your health care team will either ask you to drink about 2 cups of fluid or give it to you through an IV infusion. Because this drug leaves the body mainly through urine, this will help get the excess radiation out of the body as soon as possible.

Typically it takes 1 to 3 weeks for this drug to start to relieve bone pain.


This drug contains radiation, which will leave your body slowly over time. Ask your healthcare team if there are any restrictions about contact with other people after getting this drug. Your healthcare team will tell you to take precautions for some time after treatment to lower the chance of exposing other people to radiation. These might include using a toilet to get rid of urine, feces, and vomit whenever possible and then flushing the toilet several times after each use. Caregivers should wear gloves when handling body fluids (such as urine) or soiled clothes and wash their hands afterward.

This drug can damage your bone marrow, which is where new blood cells are made. This could lead to a drop in your blood cell counts, which might last for a month or more. In rare cases, the damage might be severe enough to be life threatening. Your doctor will check your blood cell counts before treatment to see if you can get this drug, and then again each week for at least 8 weeks after treatment. Based on the test results, you might get treatment to help with any effects. It is very important that you keep all of your appointments for lab tests and doctor visits.

This drug can lower your blood platelet count, which can raise your risk of uncontrolled bleeding. If this occurs, it will usually happen within about a month after treatment. Your doctor will check your platelet count before and after treatment. Be sure your doctor knows if you are taking any medicines that could affect your body’s ability to stop bleeding (see “Interactions with other drugs”). Tell your doctor or nurse right away if you cough up blood or have unusual bruising, nosebleeds, bleeding gums when you brush your teeth, vomit that is bloody or looks like coffee grounds, or black, tarry stools.

This drug might lower your red blood cell count. If this occurs, it will usually happen a few months after treatment. A low red blood cell count (known as anemia) can cause shortness of breath, or make you feel weak or tired all the time. Be sure to let your doctor or nurse know right away if you have any of these symptoms. If you do become anemic, you might need blood transfusions or other treatments to help with this.

This drug can lower your white blood cell count. This can increase your chance of getting an infection. If this occurs, it will usually happen within about a month after treatment. Be sure to let your doctor or nurse know right away if you have any signs of infection, such as fever (100.5° or higher), chills, pain when passing urine, new onset of cough, or bringing up sputum.

Do not get any immunizations (vaccines) after treatment with this drug without your doctor’s OK. This drug might affect your immune system. This could make vaccinations ineffective, or even lead to serious infections if you get live vaccines during treatment or for some time afterward. Try to avoid contact with people who have recently received a live virus vaccine, such as the oral polio vaccine or smallpox vaccine. Check with your doctor about this.

Other treatments for cancer, such as chemotherapy and external radiation therapy, can also lower blood cell counts. This drug should not be used along with or right after chemotherapy or radiation therapy unless your doctor feels the benefit clearly outweighs the risks.

Getting this drug might lead to low blood calcium levels (hypocalcemia). Your doctor might check your blood calcium levels after treatment if you are at risk for this. Possible symptoms could include muscle spasms or cramps, muscle or joint pains, changes in sensations on the face, hands or feet, confusion, or seizures. Tell your doctor right away if you notice any of these symptoms.

Because this drug contains radiation, it might raise the risk of getting another type of cancer, such as bone cancer, later in life. If this were to happen, it would likely be many years after treatment.

Possible side effects

You will probably not have most of the following side effects, but if you have any talk to your doctor or nurse. They can help you understand the side effects and cope with them.


  • Low blood platelet count (with increased risk of bleeding)*
  • Low red blood cell count (anemia)*
  • Low white blood cell count (with increased risk of infection)*

Less common

  • Bleeding or bruising
  • Infection


  • Temporary increase in bone pain
  • Change in heart rhythm
  • High blood pressure
  • Diarrhea
  • Problems with blood clotting
  • Bone fracture, including bones in the spine
  • Feeling dizzy
  • Stroke
  • Cough
  • Death due to severe bone marrow damage or other causes

*See the “Precautions” section for more detailed information.

There are other side effects not listed above that can also occur in some patients. Tell your doctor or nurse if you develop these or any other problems.

FDA approval

Yes – first approved in 1997

Disclaimer: This information does not cover all possible uses, actions, precautions, side effects, or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for talking with your doctor, who is familiar with your medical needs.

Last Medical Review: 05/22/2013
Last Revised: 05/22/2013