Drug · FAERS side-effect profile with label screen
Palonosetron Hydrochloride side effects: what 5,239 FDA adverse event reports show
Drug class
Serotonin-3 (5-ht 3 ) receptor antagonist
FDA label, Indications wording
Brand names
Posfrea
openFDA label
Who reports
5,239 reports · 93% serious · 892 with death outcome · 55% female
openFDA FAERS counts, all years, deduplication not applied
Used for
POSFREA is indicated in adults for prevention of: acute and delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). acute nausea and vomiting associated with initial and repeat courses highly emetogenic cancer chemotherapy (HEC). postoperative nausea and vomiting (PONV) for up to 24 hours following surgery.
FDA label, Indications and Usage
What it is
POSFREA Injection contains palonosetron as palonosetron HCl, an antiemetic and antinauseant agent. It is a serotonin-3 (5-HT 3 ) receptor antagonist with a strong binding affinity for this receptor.
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 3Labeled (related wording) 3Reporting / coding artifact 1Lab value / disease marker 4Not in label — unassessed 29
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.
- 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. 198 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 |
|---|---|---|---|---|---|---|
| Neutrophil count decreased | 235 | 23.3 20.6–26.5ROR 24.4 · χ² 4,982 / p <1e-300 | 23.2 EB05 20.8 · IC025 +4.3 3/3 methods agree | Lab value / disease marker | serious PRR 16.0 · 96% clinician | no trial data cached |
| Febrile neutropenia | 338 | 20.5 18.5–22.8ROR 21.9 · χ² 6,243 / p <1e-300 | 20.4 EB05 18.6 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 12.6 · 94% clinician | no trial data cached |
| Hair colour changes | 64 | 20.5 16.0–26.1ROR 20.7 · χ² 1,159 / p 2e-254 | 20.2 EB05 16.4 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=13 · ♀ 100% (drug 55%) | no trial data cached |
| Hair texture abnormal | 64 | 19.1 14.9–24.3ROR 19.3 · χ² 1,073 / p 1e-235 | 18.9 EB05 15.3 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=13 · ♀ 100% (drug 55%) | no trial data cached |
| Madarosis | 53 | 18.2 13.9–23.8ROR 18.4 · χ² 840 / p 5e-185 | 18.0 EB05 14.2 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=9 · ♀ 100% (drug 55%) | no trial data cached |
| Myelosuppression | 148 | 17.5 14.9–20.5ROR 18.0 · χ² 2,276 / p <1e-300 | 17.4 EB05 15.1 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious PRR 10.7 · 97% clinician | no trial data cached |
| Lymphocyte count decreased | 60 | 13.6 10.6–17.5ROR 13.8 · χ² 687 / p 1e-151 | 13.4 EB05 10.7 · IC025 +3.2 3/3 methods agree | Lab value / disease marker | serious PRR 9.9 · 100% clinician | no trial data cached |
| Hypomagnesaemia | 46 | 13.3 10.0–17.7ROR 13.4 · χ² 510 / p 4e-113 | 13.0 EB05 10.0 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 8.4 | no trial data cached |
| Cytokine release syndrome | 59 | 12.4 9.6–16.0ROR 12.6 · χ² 607 / p 3e-134 | 12.2 EB05 9.7 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 7.6 · ♀ 22% (drug 55%) · 100% clinician | no trial data cached |
| Inappropriate antidiuretic hormone secretion | 31 | 12.2 8.6–17.4ROR 12.3 · χ² 307 / p 4e-69 | 11.7 EB05 8.4 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 7.6 · ♀ 15% (drug 55%) · 100% clinician | no trial data cached |
| Hypokalaemia (low potassium) | 133 | 11.6 9.8–13.7ROR 11.9 · χ² 1,280 / p 1e-280 | 11.5 EB05 9.9 · IC025 +3.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.2 | no trial data cached |
| Bacteraemia | 34 | 11.6 8.3–16.2ROR 11.7 · χ² 318 / p 2e-71 | 11.1 EB05 8.1 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 7.0 · 94% clinician | no trial data cached |
| Mucosal inflammation | 67 | 10.3 8.1–13.1ROR 10.4 · χ² 553 / p 1e-122 | 10.0 EB05 8.1 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.6 · 95% clinician | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 323 | 9.6 8.6–10.6ROR 10.1 · χ² 2,476 / p <1e-300 | 9.5 EB05 8.6 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 6.0 · 92% clinician | no trial data cached |
| Respiratory depression | 29 | 9.5 6.6–13.6ROR 9.5 · χ² 211 / p 4e-48 | 8.7 EB05 6.2 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 6.0 · 97% clinician | no trial data cached |
| Polyneuropathy | 28 | 9.4 6.5–13.7ROR 9.5 · χ² 202 / p 3e-46 | 8.7 EB05 6.1 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 5.9 · 100% clinician | no trial data cached |
| Leukopenia (low white blood cells) | 115 | 9.2 7.7–11.1ROR 9.4 · χ² 837 / p 3e-184 | 9.0 EB05 7.7 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 5.8 · 95% clinician | no trial data cached |
| Oral candidiasis (oral thrush) | 27 | 8.3 5.7–12.1ROR 8.4 · χ² 166 / p 2e-38 | 7.5 EB05 5.3 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 6.9 · 100% clinician | no trial data cached |
| Pneumonitis | 56 | 8.3 6.4–10.8ROR 8.4 · χ² 352 / p 8e-79 | 7.9 EB05 6.3 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 5.3 · 96% clinician | no trial data cached |
| Infusion related reaction (reaction during infusion) | 136 | 8.3 7.0–9.7ROR 8.4 · χ² 860 / p 2e-189 | 8.1 EB05 7.0 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 · 98% clinician | no trial data cached |
| Ileus | 24 | 7.8 5.2–11.7ROR 7.8 · χ² 136 / p 1e-31 | 7.0 EB05 4.9 · IC025 +2.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.8 · 92% clinician | no trial data cached |
| Aspartate aminotransferase increased | 96 | 7.2 5.9–8.8ROR 7.4 · χ² 511 / p 2e-113 | 7.0 EB05 5.9 · IC025 +2.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.9 · 94% clinician | no trial data cached |
| Platelet count decreased | 190 | 7.1 6.2–8.2ROR 7.4 · χ² 1,002 / p 4e-220 | 7.0 EB05 6.2 · IC025 +2.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.2 · 94% clinician | no trial data cached |
| Upper gastrointestinal haemorrhage | 28 | 6.6 4.6–9.6ROR 6.7 · χ² 129 / p 4e-30 | 6.1 EB05 4.4 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.1 · ♀ 19% (drug 55%) | no trial data cached |
| Thrombotic microangiopathy | 16 | 6.6 4.1–10.8ROR 6.6 · χ² 71 / p 2e-17 | 5.7 EB05 3.7 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 4.1 | no trial data cached |
| Thrombocytopenia (low platelets) | 184 | 6.6 5.7–7.6ROR 6.8 · χ² 874 / p 3e-192 | 6.5 EB05 5.7 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 4.2 · 96% clinician | no trial data cached |
| Anaemia (low red blood cells) | 312 | 6.5 5.9–7.3ROR 6.9 · χ² 1,472 / p <1e-300 | 6.5 EB05 5.9 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 4.3 · 96% clinician | no trial data cached |
| Stomatitis (mouth sores) | 99 | 6.5 5.4–7.9ROR 6.6 · χ² 459 / p 3e-102 | 6.4 EB05 5.4 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 5.9 | no trial data cached |
| Neuropathy peripheral (nerve damage in hands/feet) | 151 | 6.4 5.5–7.5ROR 6.6 · χ² 684 / p 4e-151 | 6.3 EB05 5.5 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 4.4 · 94% clinician | no trial data cached |
| Interstitial lung disease | 77 | 6.4 5.1–8.0ROR 6.5 · χ² 344 / p 3e-77 | 6.2 EB05 5.1 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 3.9 · 96% clinician | no trial data cached |
| Palmar-plantar erythrodysaesthesia syndrome | 37 | 6.3 4.6–8.7ROR 6.4 · χ² 161 / p 4e-37 | 5.9 EB05 4.5 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 · ♀ 87% (drug 55%) | no trial data cached |
| Altered state of consciousness | 32 | 5.9 4.2–8.4ROR 6.0 · χ² 127 / p 1e-29 | 5.5 EB05 4.1 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 3.7 · 94% clinician | no trial data cached |
| Alanine aminotransferase increased | 91 | 5.9 4.8–7.3ROR 6.0 · χ² 369 / p 2e-82 | 5.8 EB05 4.8 · IC025 +2.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.0 · 93% clinician | no trial data cached |
| White blood cell count decreased | 157 | 5.8 5.0–6.8ROR 5.9 · χ² 620 / p 3e-137 | 5.7 EB05 5.0 · IC025 +2.2 3/3 methods agree | Lab value / disease marker | serious PRR 4.9 · 93% clinician | no trial data cached |
| Hypocalcaemia (low calcium) | 27 | 5.7 3.9–8.3ROR 5.8 · χ² 101 / p 6e-24 | 5.2 EB05 3.8 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 3.7 · 93% clinician | no trial data cached |
| Device related infection | 22 | 5.7 3.8–8.7ROR 5.7 · χ² 81 / p 1e-19 | 5.1 EB05 3.6 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 3.6 · 90% clinician | no trial data cached |
| Alopecia (hair loss) | 278 | 5.7 5.0–6.3ROR 5.9 · χ² 1,070 / p 6e-235 | 5.6 EB05 5.1 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 5.7 · ♀ 95% (drug 55%) | no trial data cached |
| Sinus tachycardia | 20 | 5.7 3.6–8.8ROR 5.7 · χ² 72 / p 1e-17 | 5.0 EB05 3.4 · IC025 +1.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.6 | no trial data cached |
| Impaired quality of life | 20 | 5.6 3.6–8.6ROR 5.6 · χ² 70 / p 2e-17 | 5.0 EB05 3.4 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 4.8 · ♀ 100% (drug 55%) | no trial data cached |
| Blood lactate dehydrogenase increased | 22 | 5.5 3.6–8.4ROR 5.5 · χ² 77 / p 9e-19 | 5.0 EB05 3.5 · IC025 +1.6 3/3 methods agree | Lab value / disease marker | serious PRR 3.6 · 95% 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 |
|---|---|---|---|---|---|---|
| Nausea | 597 | 3.0 2.8–3.3ROR 3.3 · χ² 840 / p 5e-185 | 3.0 EB05 2.8 · IC025 +1.5 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 3.3 | no trial data cached |
| Diarrhoea (diarrhea) | 366 | 2.3 2.1–2.5ROR 2.4 · χ² 269 / p 1e-60 | 2.3 EB05 2.1 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.4 | no trial data cached |
| Vomiting | 356 | 3.0 2.7–3.4ROR 3.2 · χ² 496 / p 4e-110 | 3.0 EB05 2.8 · IC025 +1.4 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 2.7 | no trial data cached |
| Febrile neutropenia | 338 | 20.5 18.5–22.8ROR 21.9 · χ² 6,243 / p <1e-300 | 20.4 EB05 18.6 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 12.6 · 94% clinician | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 323 | 9.6 8.6–10.6ROR 10.1 · χ² 2,476 / p <1e-300 | 9.5 EB05 8.6 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 6.0 · 92% clinician | no trial data cached |
| Anaemia (low red blood cells) | 312 | 6.5 5.9–7.3ROR 6.9 · χ² 1,472 / p <1e-300 | 6.5 EB05 5.9 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 4.3 · 96% clinician | no trial data cached |
| Pyrexia (fever) | 283 | 3.3 2.9–3.7ROR 3.4 · χ² 451 / p 2e-100 | 3.3 EB05 2.9 · IC025 +1.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 2.5 · 90% clinician | no trial data cached |
| Alopecia (hair loss) | 278 | 5.7 5.0–6.3ROR 5.9 · χ² 1,070 / p 6e-235 | 5.6 EB05 5.1 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 5.7 · ♀ 95% (drug 55%) | no trial data cached |
| Decreased appetite (loss of appetite) | 272 | 4.7 4.2–5.3ROR 4.9 · χ² 797 / p 1e-175 | 4.7 EB05 4.2 · IC025 +2.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.2 | no trial data cached |
| Death | 264 | 1.2 1.1–1.4ROR 1.2 · χ² 11 / p 4e-4 | 1.2 EB05 1.1 · IC025 +0.1 | Outcome field, not a reaction | serious PRR 0.8 | no trial data cached |
| Neutrophil count decreased | 235 | 23.3 20.6–26.5ROR 24.4 · χ² 4,982 / p <1e-300 | 23.2 EB05 20.8 · IC025 +4.3 3/3 methods agree | Lab value / disease marker | serious PRR 16.0 · 96% clinician | no trial data cached |
| Constipation | 212 | 3.9 3.4–4.5ROR 4.0 · χ² 463 / p 6e-103 | 3.9 EB05 3.5 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.1 · 92% clinician | no trial data cached |
| Asthenia (weakness) | 201 | 2.1 1.9–2.4ROR 2.2 · χ² 123 / p 7e-29 | 2.1 EB05 1.9 · IC025 +0.9 | Not in label — unassessed | serious PRR 1.8 | no trial data cached |
| Pneumonia (lung infection) | 199 | 2.5 2.1–2.8ROR 2.5 · χ² 174 / p 5e-40 | 2.5 EB05 2.2 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 1.6 · 94% clinician | no trial data cached |
| Platelet count decreased | 190 | 7.1 6.2–8.2ROR 7.4 · χ² 1,002 / p 4e-220 | 7.0 EB05 6.2 · IC025 +2.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.2 · 94% clinician | 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.
- Febrile neutropenia — n=338, PRR 20.5
- Hair colour changes — n=64, PRR 20.5
- Hair texture abnormal — n=64, PRR 19.1
- Madarosis — n=53, PRR 18.2
- Myelosuppression — n=148, PRR 17.5
- Hypomagnesaemia — n=46, PRR 13.3
- Cytokine release syndrome — n=59, PRR 12.4
- Inappropriate antidiuretic hormone secretion — n=31, PRR 12.2
- Bacteraemia — n=34, PRR 11.6
- Mucosal inflammation — n=67, PRR 10.3
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 Palonosetron?
In FDA FAERS, the most frequently co-reported reaction terms for Palonosetron are nausea, diarrhoea, vomiting, febrile neutropenia, neutropenia, anaemia. 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 Palonosetron have an FDA boxed warning?
No. The FDA label retrieved for Palonosetron has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Palonosetron 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 13a201ba-c86d-48c5-a0e1-a3e0b4e6a2a7, effective 20250429; matched on
openfda.generic_name.exact:"PALONOSETRON") - 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, 238 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.