Drug · FAERS side-effect profile with label screen
Naloxone side effects: what 5,672 FDA adverse event reports show
Drug class
Not stated in label
Brand names
Naloxone Hydrochloride
openFDA label
Who reports
5,672 reports · 87% serious · 1,308 with death outcome · 49% female
openFDA FAERS counts, all years, deduplication not applied
Used for
(s) to “revive” someone during an overdose from many prescription pain medications or street drugs such as heroin this medicine can save a life
FDA label, Indications and Usage
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
Reporting / coding artifact 2No label text to screen 38
What the badges mean
- 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.
- 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.
- No label text to screen No validated FDA label was retrievable for this product, so the screen could not run. Disproportionality only.
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. 347 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 |
|---|---|---|---|---|---|---|
| Respiratory depression | 163 | 49.8 42.8–58.0ROR 51.2 · χ² 7,645 / p <1e-300 | 48.9 EB05 42.9 · IC025 +5.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 33.5 · 92% clinician | no trial data cached |
| Unresponsive to stimuli | 168 | 24.3 20.9–28.2ROR 25.0 · χ² 3,709 / p <1e-300 | 24.1 EB05 21.2 · IC025 +4.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 16.3 | no trial data cached |
| Toxicity to various agents | 773 | 17.1 16.0–18.3ROR 19.6 · χ² 11,743 / p <1e-300 | 17.0 EB05 16.0 · IC025 +4.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 11.5 · 94% clinician | no trial data cached |
| Sinus tachycardia | 53 | 13.9 10.6–18.1ROR 14.0 · χ² 618 / p 9e-137 | 13.6 EB05 10.7 · IC025 +3.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 9.3 · 100% clinician | no trial data cached |
| Depressed level of consciousness | 141 | 13.2 11.3–15.6ROR 13.6 · χ² 1,582 / p <1e-300 | 13.1 EB05 11.4 · IC025 +3.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 9.0 · 92% clinician | no trial data cached |
| Transfusion | 36 | 12.7 9.2–17.6ROR 12.8 · χ² 375 / p 7e-84 | 12.3 EB05 9.1 · IC025 +2.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 8.8 | no trial data cached |
| Poisoning | 43 | 12.6 9.4–17.0ROR 12.7 · χ² 448 / p 1e-99 | 12.3 EB05 9.3 · IC025 +3.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 8.5 · ♀ 12% (drug 49%) · 90% clinician | no trial data cached |
| Drug withdrawal syndrome neonatal | 50 | 12.4 9.4–16.3ROR 12.5 · χ² 511 / p 2e-113 | 12.1 EB05 9.4 · IC025 +3.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 8.0 | no trial data cached |
| Acute respiratory failure | 58 | 11.2 8.7–14.5ROR 11.3 · χ² 529 / p 2e-117 | 10.9 EB05 8.6 · IC025 +2.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 7.4 | no trial data cached |
| Premature delivery | 48 | 11.1 8.4–14.7ROR 11.2 · χ² 431 / p 5e-96 | 10.7 EB05 8.3 · IC025 +2.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 7.5 · ♀ 100% (drug 49%) | no trial data cached |
| Pulmonary oedema | 133 | 11.0 9.3–13.0ROR 11.2 · χ² 1,198 / p 9e-263 | 10.9 EB05 9.4 · IC025 +3.1 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 7.3 · 91% clinician | no trial data cached |
| Hypoxia (low oxygen) | 102 | 10.8 8.9–13.1ROR 11.0 · χ² 894 / p 9e-197 | 10.6 EB05 8.9 · IC025 +3.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 7.2 | no trial data cached |
| Electrocardiogram qt prolonged | 104 | 10.7 8.9–13.0ROR 10.9 · χ² 905 / p 4e-199 | 10.5 EB05 8.9 · IC025 +3.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 7.2 · ♀ 81% (drug 49%) · 96% clinician | no trial data cached |
| Brain oedema | 35 | 10.3 7.4–14.3ROR 10.3 · χ² 283 / p 8e-64 | 9.7 EB05 7.1 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.8 · 100% clinician | no trial data cached |
| Coma | 125 | 9.7 8.2–11.6ROR 9.9 · χ² 968 / p 7e-213 | 9.5 EB05 8.2 · IC025 +2.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.4 · 99% clinician | no trial data cached |
| Drug abuse | 216 | 9.6 8.4–10.9ROR 9.9 · χ² 1,651 / p <1e-300 | 9.5 EB05 8.4 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 6.3 | no trial data cached |
| Mental status changes | 70 | 9.3 7.4–11.8ROR 9.4 · χ² 512 / p 1e-113 | 9.0 EB05 7.3 · IC025 +2.7 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.6 · 92% clinician | no trial data cached |
| Tachypnoea | 34 | 9.3 6.6–13.0ROR 9.3 · χ² 243 / p 4e-55 | 8.7 EB05 6.3 · IC025 +2.5 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.3 · 94% clinician | no trial data cached |
| Caesarean section | 29 | 9.1 6.4–13.1ROR 9.2 · χ² 202 / p 5e-46 | 8.4 EB05 6.0 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.2 · ♀ 100% (drug 49%) | no trial data cached |
| Serotonin syndrome | 47 | 9.1 6.8–12.1ROR 9.2 · χ² 330 / p 4e-74 | 8.6 EB05 6.7 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.1 · 100% clinician | no trial data cached |
| Cardiogenic shock | 34 | 8.8 6.3–12.3ROR 8.9 · χ² 228 / p 9e-52 | 8.2 EB05 6.0 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.8 · ♀ 73% (drug 49%) · 97% clinician | no trial data cached |
| Oral candidiasis (oral thrush) | 30 | 8.5 6.0–12.2ROR 8.6 · χ² 192 / p 6e-44 | 7.8 EB05 5.6 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 7.9 | no trial data cached |
| Delusion | 34 | 8.1 5.8–11.4ROR 8.2 · χ² 205 / p 7e-47 | 7.5 EB05 5.6 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.5 · ♀ 0% (drug 49%) | no trial data cached |
| Pulmonary congestion | 29 | 8.1 5.6–11.7ROR 8.2 · χ² 174 / p 6e-40 | 7.4 EB05 5.3 · IC025 +2.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.2 | no trial data cached |
| Overdose | 461 | 7.9 7.2–8.6ROR 8.5 · χ² 2,786 / p <1e-300 | 7.8 EB05 7.2 · IC025 +2.8 3/3 methods agree | Reporting / coding artifact | serious PRR 6.5 | no trial data cached |
| Brain injury | 21 | 7.7 5.1–11.9ROR 7.8 · χ² 117 / p 2e-27 | 6.8 EB05 4.6 · IC025 +2.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.2 | no trial data cached |
| Delirium | 72 | 7.7 6.1–9.7ROR 7.8 · χ² 414 / p 3e-92 | 7.4 EB05 6.1 · IC025 +2.5 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.1 · 97% clinician | no trial data cached |
| Cardiac arrest (heart stopping) | 171 | 7.6 6.6–8.9ROR 7.8 · χ² 983 / p 6e-216 | 7.5 EB05 6.6 · IC025 +2.7 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.1 · 90% clinician | no trial data cached |
| Premature baby | 61 | 7.5 5.8–9.6ROR 7.6 · χ² 336 / p 3e-75 | 7.1 EB05 5.7 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.0 · ♀ 25% (drug 49%) | no trial data cached |
| Respiratory failure | 147 | 7.5 6.4–8.8ROR 7.6 · χ² 817 / p 6e-180 | 7.3 EB05 6.4 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.9 · 91% clinician | no trial data cached |
| Sinus bradycardia | 19 | 7.3 4.6–11.4ROR 7.3 · χ² 96 / p 5e-23 | 6.3 EB05 4.2 · IC025 +1.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.9 | no trial data cached |
| Renal tubular necrosis | 19 | 7.2 4.6–11.2ROR 7.2 · χ² 94 / p 1e-22 | 6.2 EB05 4.2 · IC025 +1.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.8 | no trial data cached |
| Encephalopathy | 47 | 7.1 5.3–9.4ROR 7.2 · χ² 240 / p 2e-54 | 6.7 EB05 5.2 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.7 · 96% clinician | no trial data cached |
| Metabolic acidosis | 60 | 7.0 5.5–9.0ROR 7.1 · χ² 304 / p 3e-68 | 6.7 EB05 5.4 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.7 · 97% clinician | no trial data cached |
| Metastases to bone | 31 | 7.0 4.9–10.0ROR 7.0 · χ² 154 / p 1e-35 | 6.4 EB05 4.7 · IC025 +2.1 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.7 | no trial data cached |
| Clostridium difficile colitis | 20 | 7.0 4.5–10.8ROR 7.0 · χ² 96 / p 5e-23 | 6.1 EB05 4.1 · IC025 +1.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.7 | no trial data cached |
| Drug toxicity | 25 | 6.7 4.5–9.9ROR 6.7 · χ² 115 / p 3e-27 | 6.0 EB05 4.3 · IC025 +1.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.6 | no trial data cached |
| End stage renal disease | 33 | 6.6 4.7–9.3ROR 6.7 · χ² 152 / p 3e-35 | 6.1 EB05 4.5 · IC025 +2.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.4 · ♀ 26% (drug 49%) | no trial data cached |
| Paranoia | 31 | 6.6 4.7–9.4ROR 6.7 · χ² 142 / p 4e-33 | 6.1 EB05 4.5 · IC025 +2.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.3 · ♀ 0% (drug 49%) | no trial data cached |
| Leukocytosis | 32 | 6.6 4.6–9.3ROR 6.6 · χ² 145 / p 1e-33 | 6.0 EB05 4.5 · IC025 +2.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.4 · 90% 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 |
|---|---|---|---|---|---|---|
| Toxicity to various agents | 773 | 17.1 16.0–18.3ROR 19.6 · χ² 11,743 / p <1e-300 | 17.0 EB05 16.0 · IC025 +4.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 11.5 · 94% clinician | no trial data cached |
| Drug ineffective (drug did not work) | 568 | 1.6 1.5–1.7ROR 1.7 · χ² 134 / p 3e-31 | 1.6 EB05 1.5 · IC025 +0.5 | Reporting / coding artifact | serious PRR 2.8 | no trial data cached |
| Overdose | 461 | 7.9 7.2–8.6ROR 8.5 · χ² 2,786 / p <1e-300 | 7.8 EB05 7.2 · IC025 +2.8 3/3 methods agree | Reporting / coding artifact | serious PRR 6.5 | no trial data cached |
| Vomiting | 256 | 2.0 1.8–2.3ROR 2.1 · χ² 134 / p 3e-31 | 2.0 EB05 1.8 · IC025 +0.8 | No label text to screen label has no adverse-reaction text | serious PRR 1.7 | no trial data cached |
| Death | 251 | 1.1 1.0–1.2ROR 1.1 · χ² 1 / p 0.120 | 1.1 EB05 1.0 · IC025 -0.1 PRR-only: not supported by EBGM or IC | Outcome field, not a reaction | serious PRR 0.7 | no trial data cached |
| Acute kidney injury (sudden kidney damage) | 232 | 5.6 5.0–6.4ROR 5.8 · χ² 886 / p 6e-195 | 5.6 EB05 5.0 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 3.7 | no trial data cached |
| Hypotension (low blood pressure) | 217 | 4.0 3.5–4.6ROR 4.1 · χ² 491 / p 4e-109 | 4.0 EB05 3.6 · IC025 +1.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 3.0 | no trial data cached |
| Drug abuse | 216 | 9.6 8.4–10.9ROR 9.9 · χ² 1,651 / p <1e-300 | 9.5 EB05 8.4 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 6.3 | no trial data cached |
| Somnolence (drowsiness) | 198 | 3.6 3.2–4.2ROR 3.7 · χ² 380 / p 5e-85 | 3.6 EB05 3.2 · IC025 +1.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 3.9 | no trial data cached |
| Drug dependence | 172 | 3.9 3.4–4.5ROR 4.0 · χ² 372 / p 3e-83 | 3.9 EB05 3.4 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 2.5 | no trial data cached |
| Cardiac arrest (heart stopping) | 171 | 7.6 6.6–8.9ROR 7.8 · χ² 983 / p 6e-216 | 7.5 EB05 6.6 · IC025 +2.7 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.1 · 90% clinician | no trial data cached |
| Drug interaction | 169 | 3.9 3.4–4.6ROR 4.0 · χ² 370 / p 8e-83 | 3.9 EB05 3.4 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 2.9 · 93% clinician | no trial data cached |
| Unresponsive to stimuli | 168 | 24.3 20.9–28.2ROR 25.0 · χ² 3,709 / p <1e-300 | 24.1 EB05 21.2 · IC025 +4.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 16.3 | no trial data cached |
| Respiratory depression | 163 | 49.8 42.8–58.0ROR 51.2 · χ² 7,645 / p <1e-300 | 48.9 EB05 42.9 · IC025 +5.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 33.5 · 92% clinician | no trial data cached |
| Drug withdrawal syndrome | 156 | 6.5 5.6–7.6ROR 6.7 · χ² 724 / p 9e-160 | 6.4 EB05 5.6 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.6 | no trial data cached |
Unlabeled candidate signals
Every screened signal with n ≥ 20 was either labeled, an indication term, or an artifact pattern — no unlabeled candidate stood out in the top signals.
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 Naloxone?
In FDA FAERS, the most frequently co-reported reaction terms for Naloxone are toxicity to various agents, vomiting, acute kidney injury, hypotension, somnolence, cardiac arrest. 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 Naloxone have an FDA boxed warning?
No. The FDA label retrieved for Naloxone has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Naloxone 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 8779a073-dc6e-410a-9959-fd370f0079f9, effective 20240419; matched on
openfda.generic_name.exact:"NALOXONE") - 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, 387 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.