Tositumomab and Iodine I 131 Tositumomab (Generic Name)

Other Names: BEXXAR®

About this drug

The drug tositumomab and iodine I 131 tositumomab is used to treat cancer. It is a combination of tositumomab, a special type of antibody used to treat cancer, and iodine I 131, a radioactive element that has been shown to be effective against cancer. This drug is given intravenously (IV).

Allergic reactions

Serious allergic reactions may occur during the time you are receiving this drug by IV infusion. While receiving this drug, tell your doctor or nurse immediately if you have any of the following symptoms:

  • Difficulty catching your breath
  • Feeling like your tongue or throat is swelling
  • Feeling your heart beat rapidly (palpitations)
  • Dizziness or lightheadedness

Possible side effects

Less serious reactions to this drug may occur. You will be given medicine to help prevent or lessen these symptoms. Your vital signs will be monitored during the infusion.

Tell your doctor or nurse immediately if you have any of the following symptoms at any time during the infusion or for the first 48 hours after receiving this drug:

  • Fever, chills, or shaking chills
  • Sweating
  • Hives, itchy skin, or rash
  • Flushing
  • Trouble breathing
  • Headache
  • Runny nose
  • Nausea or vomiting
  • Dizziness or lightheadedness
  • Abdominal or back pain
  • Weakness
  • Throat irritation
  • Cough

For as long as 14 days after you receive the drug, you may experience fever, chills, or sweating.

Other possible side effects may include:

  • Bone marrow depression. This is a decrease in the number of white blood cells, red blood cells, and platelets. It may increase your risk for infection, fatigue, and bleeding. The bone marrow depression may occur as late as 3 months following treatment and last for several months.
  • Effects on the thyroid gland. You will be given medicine to help protect your thyroid gland. It is very important that you take this medicine as directed by your doctor. Your doctor will monitor your thyroid function as needed.
  • Diarrhea
  • Loss of appetite
  • Soreness in muscles and joints
  • Development of a new blood-related cancer. This is very rare.
  • Effects on an unborn child. This drug may have harmful effects on an unborn child. Use effective methods of birth control during your cancer treatment. Genetic counseling is available to you to talk about the effect of this drug therapy on future pregnancies. A genetic counselor can review the potential risks to the fetus if you are exposed to this medicine during pregnancy.
  • Sexual problems and reproductive concerns. In men and women, this drug may temporarily or permanently affect your ability to have children. This cannot be determined before your therapy. In men, this drug may interfere with your ability to make sperm, but it should not change your ability to have sexual relations.

    Ask your doctor about sperm banking if you think you might want to have children later. In women, menstrual bleeding may become irregular or stop while you are receiving this drug. However, even if you do not have a menstrual period, it is still possible to become pregnant. Women may also have signs of menopause like vaginal dryness or itching.

Treating side effects

  • Ask your doctor or nurse about medicine to help prevent or lessen nausea, vomiting, headache, muscle and joint soreness, and diarrhea.
  • Use effective methods of birth control during your cancer treatment.

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