The most commonly reported side effects of trastuzumab include diarrhoea, nausea, and off label use, based on 85,357 FDA adverse event reports from 2004 to 2025.
Percentages show how often each reaction appears relative to total reports for trastuzumab.
These are voluntary reports and do not establish that trastuzumab caused these reactions.
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Other drugs that appear in adverse event reports alongside trastuzumab. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.
Also suspected
Taken alongside
Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.
79.2% of trastuzumab adverse event reports involve female patients and 6.2% involve male patients. The largest age group is adult at 72%. These figures reflect who reports side effects, not underlying risk.
Sex
Age group
Conditions and purposes for which patients were taking trastuzumab when the adverse event was reported.
Showing 15 of 901 indications
Trastuzumab is sold under several brand names including Herceptin, Kadcyla, Enhertu.
An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.
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