OpenClaim

Zanidatamab Side Effects

The most commonly reported side effects of zanidatamab include diarrhoea, infusion related reaction, and sepsis, based on 185 FDA adverse event reports from 2005 to 2025.

Zanidatamab side effects

Percentages show how often each reaction appears relative to total reports for zanidatamab.

1
Diarrhoea29.2%54
2
Infusion Related Reaction11.9%22
3
Sepsis5.4%10
4
Pneumonitis4.9%9
5
Pneumonia4.3%8
6
Acute Kidney Injury4.3%8
7
Off Label Use4.3%8
8
Hypokalaemia4.3%8
9
Decreased Appetite3.8%7
10
Vomiting3.8%7
11
Chills3.8%7
12
Cerebrovascular Accident3.8%7
13
Nausea3.2%6
14
Disease Progression3.2%6
15
Stress Cardiomyopathy3.2%6

These are voluntary reports and do not establish that zanidatamab caused these reactions.

Report severity

89.2%Serious165 reports
69.2%Hospitalizations128 reports
9.7%Fatal18 reports

Seriousness is determined by the reporter, not by OpenClaim.

Zanidatamab drug interactions

Other drugs that appear in adverse event reports alongside zanidatamab. 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

1
Capecitabine61.6%114
2
Oxaliplatin55.7%103
3
Tislelizumab-jsgr44.3%82
4
Loperamide-hydrochloride36.2%67
5
Islelizumab-jsgr3.8%7
6
Venetoclax3.2%6
7
Azacitidine3.2%6
8
Trastuzumab2.7%5
9
Cisplatin2.2%4
10
Paclitaxel1.6%3
11
Palbociclib1.1%2
12
Fulvestrant1.1%2
13
Gemcitabine1.1%2
14
Hydrochlorothiazide1.1%2
15
Pantoprazole-sodium1.1%2

Taken alongside

1
Acetaminophen20.0%37
2
Dexamethasone18.4%34
3
Loperamide-hydrochloride17.3%32
4
Metoclopramide-hydrochloride13.0%24
5
Omeprazole11.9%22
6
Pregabalin8.6%16
7
Morphine-sulfate8.6%16
8
Aminophylline8.1%15
9
Celecoxib8.1%15
10
Cyanocobalamin7.6%14
11
Atorvastatin-calcium7.0%13
12
Sodium-chloride7.0%13
13
Pantoprazole-sodium6.5%12
14
Aluminum-hydroxide6.5%12
15
Magnesium-trisilicate6.5%12

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.

Who reports zanidatamab side effects

38.4% of zanidatamab adverse event reports involve female patients and 46.5% involve male patients. The largest age group is elderly at 57%. These figures reflect who reports side effects, not underlying risk.

Sex

Female38.4%
Male46.5%
Unknown15.1%

Age group

< 20.0%
2–110.0%
12–170.0%
18–6443.1%
65+56.9%

What is zanidatamab used for

Conditions and purposes for which patients were taking zanidatamab when the adverse event was reported.

Adenocarcinoma GastricBile Duct CancerBile Duct Cancer Stage IvBreast CancerBreast Cancer FemaleCholangiocarcinomaGallbladder CancerGastric CancerGastrointestinal AdenocarcinomaGastrooesophageal CancerGastrooesophageal Reflux DiseaseHer2 Positive Biliary Tract CancerHer2 Positive Breast CancerHepatic NeoplasmMetastases To Liver

Showing 15 of 21 indications

Zanidatamab brand names and reporting trend

Zanidatamab is sold under the brand name Ziihera.

Brand names

Ziihera278

Quarterly reports (20052025)

20052025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking zanidatamab with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.