Tositumomab Side Effects

Applies to tositumomab: intravenous solution.

Precautions

It is very important that your doctor check you closely while you are receiving this medicine. This is to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. You should not become pregnant while you are receiving this medicine and for 12 months after stopping it. Male patients should also use effective contraception to prevent pregnancy while receiving this medicine and for 12 months after stopping it. Tell your doctor right away if you become pregnant while using the medicine.

This medicine may cause serious allergic reactions, including anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a rash, itching, fever or chills, lightheadedness or dizziness, nausea, trouble breathing, or any swelling of your hands, face, mouth, or throat during treatment or within 48 hours receiving this medicine.

Tositumomab and iodine I 131 tositumomab regimen can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

• Avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
• Check with your doctor immediately if you notice any unusual bleeding or bruising; black, tarry stools; blood in the urine or stools; or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
• Avoid sports or other situations where bruising or injury could occur.

While using this medicine, you may be exposed to radiation. Talk with your doctor if you have concerns about this.

This medicine may increase your risk for certain types of cancer or thyroid problems. Talk with your doctor about these risks.

While you are being treated with tositumomab and iodine I 131 tositumomab regimen, and after you stop treatment with it, do not have any immunizations (live vaccines) without your doctor's approval. Tositumomab and iodine I 131 tositumomab may lower your body's resistance and there is a chance you might get the infection the immunization is meant to prevent.

If you plan to have children, talk with your doctor before using this medicine. Some men and women using this medicine have become infertile (unable to have children).

Serious side effects of tositumomab

Along with its needed effects, tositumomab may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking tositumomab:

Other side effects of tositumomab

Some side effects of tositumomab may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to tositumomab: intravenous kit.

Cardiovascular adverse events

• Common (1% to 10%): Hypotension, vasodilation^[Ref]

Dermatologic

• Very common (10% or more): Rash, pruritus
• Common (1% to 10%): Sweating^[Ref]

Endocrine

• Common (1% to 10%): Hypothyroidism^[Ref]

Gastrointestinal

• Very common (10% or more): Abdominal pain, nausea, vomiting, diarrhea, anorexia
• Common (1% to 10%): Constipation, dyspepsia^[Ref]

Hematologic

• Very common (10% or more): Neutropenia, thrombocytopenia, anemia^[Ref]

Hypersensitivity

• Common (1% to 10%): Allergic (hypersensitivity) reactions (allergic reaction, facial edema, injection site hypersensitivity, anaphylactic reaction, laryngismus, serum sickness)
• Postmarketing reports: Hypersensitivity reactions including fatal anaphylaxis^[Ref]

Immunologic

• Very common (10% or more): Positive serology for human anti-mouse antibodies (HAMA)^[Ref]

Local

• Frequency not reported: Infusion reactions^[Ref]

Metabolic

• Common (1% to 10%): Peripheral edema, weight loss^[Ref]

Musculoskeletal

• Very common (10% or more): Myalgia, arthralgia
• Common (1% to 10%): Back pain, neck pain^[Ref]

Nervous system

• Common (1% to 10%): Dizziness, somnolence
• Postmarketing reports: Axonal neuropathy leading to quadriparesis^[Ref]

Oncologic

• Common (1% to 10%): Secondary malignancies (non-melanoma skin, colorectal, head and neck, breast, lung, bladder, melanoma, gastric)
• Frequency not reported: Secondary leukemia, myelodysplastic syndrome^[Ref]

Other

• Very common (10% or more): Asthenia, fever, infections, pain, chills, headache
• Common (1% to 10%): Chest pain, serious infections (pneumonia, bacteremia, septicemia, bronchitis, skin infections)^[Ref]

Respiratory

• Very common (10% or more): Cough, pharyngitis, dyspnea, rhinitis
• Common (1% to 10%): Pneumonia^[Ref]

See also:

Further information

Tositumomab side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer