Drug · FAERS side-effect profile with label screen
Neratinib side effects: what 2,294 FDA adverse event reports show
Drug class
Kinase inhibitor
FDA label, Indications wording
Brand names
Nerlynx
openFDA label
Who reports
2,294 reports · 59% serious · 360 with death outcome · 96% female
openFDA FAERS counts, all years, deduplication not applied
Used for
NERLYNX is a kinase inhibitor indicated: As a single agent, for the extended adjuvant treatment of adult patients with early-stage HER2-positive breast cancer, to follow adjuvant trastuzumab-based therapy. ( 1.1 ) In combination with capecitabine, for .
FDA label, Indications and Usage
What it is
NERLYNX (neratinib) immediate release, film-coated tablets for oral administration contain 40 mg of neratinib, equivalent to 48.31 mg neratinib maleate. Neratinib is a member of the 4-anilino quinolidine class of protein kinase inhibitors.
FDA label, Description section
Boxed warning
None in the current label
How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation.
Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)?
That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.
Causality screen of the 40 strongest signals
Labeled adverse reaction 14Labeled (related wording) 2Likely indication confounding 1Reporting / coding artifact 5Lab value / disease marker 2Not in label — unassessed 16
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 33 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Breast cancer metastatic | 70 | 60.0 47.6–75.7ROR 61.9 · χ² 3,980 / p <1e-300 | 58.7 EB05 48.1 · IC025 +5.0 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 54.3 | no trial data cached |
| Metastases to central nervous system | 43 | 30.8 22.9–41.4ROR 31.4 · χ² 1,206 / p 1e-264 | 30.3 EB05 23.4 · IC025 +4.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 28.9 | no trial data cached |
| Ejection fraction decreased | 49 | 28.9 21.9–38.1ROR 29.5 · χ² 1,287 / p 5e-282 | 28.5 EB05 22.4 · IC025 +4.0 3/3 methods agree | Lab value / disease marker | serious PRR 29.7 · 98% clinician | no trial data cached |
| Appendicitis | 23 | 22.7 15.1–34.1ROR 22.9 · χ² 454 / p 5e-101 | 22.2 EB05 15.6 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 21.4 · 91% clinician | no trial data cached |
| Diarrhoea (diarrhea) | 1,249 | 17.8 17.1–18.5ROR 37.8 · χ² 20,352 / p <1e-300 | 17.7 EB05 16.9 · IC025 +4.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.1 | no trial data cached |
| Prescribed underdose | 38 | 17.4 12.7–23.9ROR 17.7 · χ² 572 / p 9e-127 | 17.2 EB05 13.0 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 23.7 | no trial data cached |
| Mucosal inflammation | 40 | 14.0 10.3–19.1ROR 14.3 · χ² 472 / p 7e-105 | 13.8 EB05 10.4 · IC025 +3.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 13.5 · 100% clinician | no trial data cached |
| Hypokalaemia (low potassium) | 68 | 13.6 10.7–17.1ROR 13.9 · χ² 779 / p 9e-172 | 13.4 EB05 10.9 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 13.2 | no trial data cached |
| Blood potassium decreased | 41 | 12.5 9.2–16.9ROR 12.7 · χ² 421 / p 7e-94 | 12.1 EB05 9.1 · IC025 +2.9 3/3 methods agree | Lab value / disease marker | serious PRR 11.1 | no trial data cached |
| Disease progression | 157 | 12.2 10.5–14.2ROR 13.0 · χ² 1,608 / p <1e-300 | 12.1 EB05 10.6 · IC025 +3.3 3/3 methods agree | Reporting / coding artifact | serious PRR 12.9 · 93% clinician | no trial data cached |
| Hypomagnesaemia | 18 | 11.9 7.5–18.8ROR 12.0 · χ² 168 / p 8e-39 | 10.9 EB05 6.8 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 11.9 | no trial data cached |
| Aphonia | 18 | 11.8 7.5–18.7ROR 11.9 · χ² 167 / p 1e-38 | 10.8 EB05 6.7 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 21.5 | no trial data cached |
| Constipation | 277 | 11.7 10.5–13.1ROR 13.2 · χ² 2,728 / p <1e-300 | 11.7 EB05 10.5 · IC025 +3.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.7 · 92% clinician | no trial data cached |
| Metastases to lung | 14 | 11.1 6.6–18.7ROR 11.2 · χ² 119 / p 6e-28 | 9.6 EB05 5.6 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 10.1 | no trial data cached |
| Lacrimation increased | 34 | 10.4 7.5–14.5ROR 10.6 · χ² 280 / p 4e-63 | 9.8 EB05 7.2 · IC025 +2.6 3/3 methods agree | Not in label — unassessed | serious PRR 25.6 · 94% clinician | no trial data cached |
| Dehydration | 147 | 10.1 8.6–11.8ROR 10.7 · χ² 1,200 / p 3e-263 | 9.9 EB05 8.6 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.1 | no trial data cached |
| Decreased appetite (loss of appetite) | 253 | 10.0 8.9–11.2ROR 11.1 · χ² 2,060 / p <1e-300 | 9.9 EB05 8.9 · IC025 +3.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.8 · 92% clinician | no trial data cached |
| Palmar-plantar erythrodysaesthesia syndrome | 24 | 9.4 6.3–14.0ROR 9.5 · χ² 172 / p 2e-39 | 8.5 EB05 5.8 · IC025 +2.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.6 · 100% clinician | no trial data cached |
| Hospice care | 10 | 9.3 5.0–17.2ROR 9.3 · χ² 66 / p 2e-16 | 7.3 EB05 4.0 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 9.2 | no trial data cached |
| Colitis | 38 | 9.2 6.7–12.7ROR 9.4 · χ² 271 / p 4e-61 | 8.7 EB05 6.5 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 9.4 · 97% clinician | no trial data cached |
| Dyspepsia (indigestion) | 98 | 9.1 7.5–11.1ROR 9.5 · χ² 705 / p 1e-155 | 8.9 EB05 7.5 · IC025 +2.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.4 · 93% clinician | no trial data cached |
| Neuropathy peripheral (nerve damage in hands/feet) | 94 | 9.1 7.5–11.1ROR 9.4 · χ² 672 / p 2e-148 | 8.9 EB05 7.4 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 9.5 · 97% clinician | no trial data cached |
| Underdose | 70 | 8.8 7.0–11.0ROR 9.0 · χ² 475 / p 1e-105 | 8.5 EB05 6.9 · IC025 +2.7 3/3 methods agree | Reporting / coding artifact | serious PRR 26.0 | no trial data cached |
| Metastases to bone | 15 | 8.4 5.1–13.9ROR 8.4 · χ² 90 / p 1e-21 | 7.1 EB05 4.4 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 8.3 | no trial data cached |
| Rash pruritic | 49 | 8.3 6.3–11.0ROR 8.5 · χ² 308 / p 3e-69 | 7.9 EB05 6.1 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.8 · 98% clinician | no trial data cached |
| Stomatitis (mouth sores) | 54 | 8.1 6.3–10.6ROR 8.3 · χ² 332 / p 2e-74 | 7.8 EB05 6.1 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.2 | no trial data cached |
| Impaired quality of life | 11 | 7.0 3.9–12.6ROR 7.0 · χ² 51 / p 6e-13 | 5.6 EB05 3.3 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 9.2 | no trial data cached |
| Product prescribing error | 18 | 7.0 4.4–11.0ROR 7.0 · χ² 86 / p 9e-21 | 6.0 EB05 4.0 · IC025 +1.8 3/3 methods agree | Reporting / coding artifact | serious PRR 13.4 | no trial data cached |
| Dementia | 21 | 6.9 4.5–10.6ROR 7.0 · χ² 100 / p 7e-24 | 6.1 EB05 4.2 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.9 · 100% clinician | no trial data cached |
| Metastases to liver | 13 | 6.8 3.9–11.7ROR 6.8 · χ² 58 / p 1e-14 | 5.6 EB05 3.5 · IC025 +1.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.7 | no trial data cached |
| Nausea | 554 | 6.4 6.0–6.9ROR 8.1 · χ² 2,628 / p <1e-300 | 6.4 EB05 6.0 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.1 · 91% clinician | no trial data cached |
| Skin fissures | 13 | 6.3 3.7–10.8ROR 6.3 · χ² 53 / p 2e-13 | 5.3 EB05 3.3 · IC025 +1.5 3/3 methods agree | Labeled adverse reaction exact term | serious n=8 | no trial data cached |
| Vomiting | 313 | 6.1 5.5–6.8ROR 6.9 · χ² 1,361 / p 3e-298 | 6.1 EB05 5.5 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.7 | no trial data cached |
| Musculoskeletal chest pain | 10 | 5.9 3.2–11.0ROR 5.9 · χ² 36 / p 1e-9 | 4.8 EB05 2.8 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | serious PRR 6.6 | no trial data cached |
| Abdominal distension (bloating) | 67 | 5.9 4.7–7.5ROR 6.0 · χ² 269 / p 1e-60 | 5.7 EB05 4.6 · IC025 +2.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.4 | no trial data cached |
| Cholelithiasis | 20 | 5.6 3.6–8.6ROR 5.6 · χ² 71 / p 2e-17 | 5.0 EB05 3.4 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 5.4 | no trial data cached |
| Fatigue (tiredness) | 473 | 5.6 5.1–6.0ROR 6.8 · χ² 1,835 / p <1e-300 | 5.5 EB05 5.1 · IC025 +2.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 · 92% clinician | no trial data cached |
| Malignant neoplasm progression | 62 | 5.6 4.4–7.1ROR 5.7 · χ² 229 / p 6e-52 | 5.4 EB05 4.3 · IC025 +2.0 3/3 methods agree | Reporting / coding artifact | serious PRR 5.5 | no trial data cached |
| Throat irritation | 27 | 5.5 3.8–8.0ROR 5.6 · χ² 96 / p 7e-23 | 5.1 EB05 3.7 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 12.0 · 100% clinician | no trial data cached |
| Hospitalisation | 91 | 5.5 4.5–6.7ROR 5.6 · χ² 329 / p 6e-74 | 5.3 EB05 4.5 · IC025 +2.1 3/3 methods agree | Reporting / coding artifact | serious PRR 5.5 · 96% clinician | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Trial cross-check not yet run for this drug (ClinicalTrials.gov pull covers the 800 most-reported drugs first).
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Diarrhoea (diarrhea) | 1,249 | 17.8 17.1–18.5ROR 37.8 · χ² 20,352 / p <1e-300 | 17.7 EB05 16.9 · IC025 +4.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.1 | no trial data cached |
| Nausea | 554 | 6.4 6.0–6.9ROR 8.1 · χ² 2,628 / p <1e-300 | 6.4 EB05 6.0 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.1 · 91% clinician | no trial data cached |
| Fatigue (tiredness) | 473 | 5.6 5.1–6.0ROR 6.8 · χ² 1,835 / p <1e-300 | 5.5 EB05 5.1 · IC025 +2.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 · 92% clinician | no trial data cached |
| Off label use (used outside approved label) | 410 | 4.3 4.0–4.7ROR 5.0 · χ² 1,087 / p 9e-239 | 4.3 EB05 4.0 · IC025 +1.9 3/3 methods agree | Reporting / coding artifact | serious PRR 7.0 | no trial data cached |
| Vomiting | 313 | 6.1 5.5–6.8ROR 6.9 · χ² 1,361 / p 3e-298 | 6.1 EB05 5.5 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.7 | no trial data cached |
| Constipation | 277 | 11.7 10.5–13.1ROR 13.2 · χ² 2,728 / p <1e-300 | 11.7 EB05 10.5 · IC025 +3.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.7 · 92% clinician | no trial data cached |
| Decreased appetite (loss of appetite) | 253 | 10.0 8.9–11.2ROR 11.1 · χ² 2,060 / p <1e-300 | 9.9 EB05 8.9 · IC025 +3.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.8 · 92% clinician | no trial data cached |
| Disease progression | 157 | 12.2 10.5–14.2ROR 13.0 · χ² 1,608 / p <1e-300 | 12.1 EB05 10.6 · IC025 +3.3 3/3 methods agree | Reporting / coding artifact | serious PRR 12.9 · 93% clinician | no trial data cached |
| Dehydration | 147 | 10.1 8.6–11.8ROR 10.7 · χ² 1,200 / p 3e-263 | 9.9 EB05 8.6 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.1 | no trial data cached |
| Dyspepsia (indigestion) | 98 | 9.1 7.5–11.1ROR 9.5 · χ² 705 / p 1e-155 | 8.9 EB05 7.5 · IC025 +2.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.4 · 93% clinician | no trial data cached |
| Neuropathy peripheral (nerve damage in hands/feet) | 94 | 9.1 7.5–11.1ROR 9.4 · χ² 672 / p 2e-148 | 8.9 EB05 7.4 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 9.5 · 97% clinician | no trial data cached |
| Hospitalisation | 91 | 5.5 4.5–6.7ROR 5.6 · χ² 329 / p 6e-74 | 5.3 EB05 4.5 · IC025 +2.1 3/3 methods agree | Reporting / coding artifact | serious PRR 5.5 · 96% clinician | no trial data cached |
| Underdose | 70 | 8.8 7.0–11.0ROR 9.0 · χ² 475 / p 1e-105 | 8.5 EB05 6.9 · IC025 +2.7 3/3 methods agree | Reporting / coding artifact | serious PRR 26.0 | no trial data cached |
| Breast cancer metastatic | 70 | 60.0 47.6–75.7ROR 61.9 · χ² 3,980 / p <1e-300 | 58.7 EB05 48.1 · IC025 +5.0 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 54.3 | no trial data cached |
| Hypokalaemia (low potassium) | 68 | 13.6 10.7–17.1ROR 13.9 · χ² 779 / p 9e-172 | 13.4 EB05 10.9 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 13.2 | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Appendicitis — n=23, PRR 22.7
- Prescribed underdose — n=38, PRR 17.4
- Hypokalaemia — n=68, PRR 13.6
- Lacrimation increased — n=34, PRR 10.4
- Colitis — n=38, PRR 9.2
- Neuropathy peripheral — n=94, PRR 9.1
- Dementia — n=21, PRR 6.9
- Cholelithiasis — n=20, PRR 5.6
- Throat irritation — n=27, PRR 5.5
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Neratinib?
In FDA FAERS, the most frequently co-reported reaction terms for Neratinib are diarrhoea, nausea, fatigue, vomiting, constipation, decreased appetite. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Neratinib have an FDA boxed warning?
No. The FDA label retrieved for Neratinib has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Neratinib causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID d1e41dcf-e82a-47c2-a0ad-6c6eef621834, effective 20260702; matched on
openfda.generic_name.exact:"NERATINIB") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 73 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.