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Tositumomab Side Effects

For the Consumer

Applies to tositumomab: parenteral iodine i 131 tositumomab injection, parenteral tositumomab injection

Side effects include:

Neutropenia, thrombocytopenia, anemia, asthenia, infection, fever, nausea.

For Healthcare Professionals

Applies to tositumomab: intravenous kit


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


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


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


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


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


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]


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


Frequency not reported: Infusion reactions[Ref]


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


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]


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]


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]


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


1. "Product Information. Bexxar I 131 Therapeutic (iodine I 131 tositumomab)." GlaxoSmithKline, Research Triangle Park, NC.

2. "Product Information. BexxarTherapy (tositumomab)." GlaxoSmithKline Inc, Oakville, IA.

It is possible that some side effects of tositumomab may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.