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Tositumomab Side Effects

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.

Some side effects of tositumomab may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

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