Samarium Sm 153 Lexidronam

Mechanism of Action

Tetraphosphonate chelating agent that concentrates in bone - precise mechanism unknown

Pharmacokinetics

Metabolism: None

Excretion: urine 20-50%

Overdosage with QUADRAMET® (samarium sm 153 lexidronam) has not been reported. An antidote for QUADRAMET® (samarium sm 153 lexidronam) overdosage is not known. The anticipated complications of overdosage would likely be secondary to bone marrow suppression from the radioactivity of 153Sm, or secondary to hypocalcemia and cardiac arrhythmias related to the EDTMP.

• Tell all of your health care providers that you take samarium sm 153 lexidronam. This includes your doctors, nurses, pharmacists, and dentists.
• If you have a latex allergy, talk with your doctor.
• It may take a few weeks to see the full effect.
• You may have more chance of getting an infection. Wash hands often. Stay away from people with infections, colds, or flu.
• You may bleed more easily. Be careful and avoid injury. Use a soft toothbrush and an electric razor.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• This medicine is radioactive. You will need to follow what the doctor has told you to lessen being exposed to this medicine. Talk with the doctor.
• Empty your bladder often for the first 12 hours after getting samarium sm 153 lexidronam.
• Use the toilet instead of a urinal.
• Use the same toilet each time you use the bathroom in your home. Sit down on the toilet to urinate to keep urine from splashing or spraying. Flush the toilet a few times after each use.
• Clean up any spilled urine right away. Wash your hands well after cleaning up.
• If blood or urine gets onto clothing, wash the clothing by itself. You may also store the clothing for 1 to 2 weeks until the drug goes away.
• If you are a man and have sex with a female who could get pregnant, protect her from pregnancy during care and for some time after care ends. Use birth control that you can trust. Talk with your doctor to see how long to use birth control after you stop this medicine.
• This medicine may cause harm to the unborn baby if you take it while you are pregnant.
• A pregnancy test will be done to show that you are NOT pregnant before starting samarium sm 153 lexidronam. If you get pregnant while taking this medicine, call your doctor right away.
• Use birth control that you can trust to prevent pregnancy during care and for some time after care ends. Talk with your doctor to see how long to use birth control after you stop samarium sm 153 lexidronam.

• If you need to store samarium sm 153 lexidronam at home, talk with your doctor, nurse, or pharmacist about how to store it.

• 153Sm-Lexidronam
• Samarium-153 Lexidronam

Note: Dose adjustments for extremes of weight have not been studied; use caution when determining dose for very thin or obese patients.

Osteoblastic metastatic bone lesion pain: IV: 1 mCi/kg (37 MBq/kg)

There are no dosage adjustments provided in the manufacturer's labeling (has not been studied); use with caution, patients with renal insufficiency may not tolerate the recommended hydration.

Store frozen at -10°C to -20°C (14°F to -4°F) in a lead-shielded container. Product expires within 56 hours of calibration or within 8 hours of thawing, whichever occurs earlier.

CBC with differential and platelets weekly for at least 8 weeks (or until adequate marrow recovery); signs/symptoms of disseminated intravascular coagulation (DIC); signs/symptoms of hypocalcemia (in patients at risk for developing hypocalcemia); fluid status in patients with renal insufficiency or heart failure

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience diarrhea or increased bone pain. Have patient report immediately to prescriber signs of infection, signs of bleeding (vomiting blood or vomit that looks like coffee grounds; coughing up blood; blood in the urine; black, red, or tarry stools; bleeding from the gums; abnormal vaginal bleeding; bruises without a reason or that get bigger; or any bleeding that is very bad or that will not stop), severe loss of strength and energy, arrhythmia, or burning or numbness feeling (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.