Haloperidol Lactate side effects: what 24,613 FDA adverse event reports show
Drug class
Not stated in label
Who reports
24,613 reports · 93% serious · 4,091 with death outcome · 44% female
Used for
Haloperidol injection is indicated for the treatment of patients with schizophrenia.
What it is
DESCRIPTION Haloperidol is the first of the butyrophenone series of major antipsychotics. The chemical designation is 4-[4-(p-chlorophenyl)-4-hydroxypiperidino]-4'-fluorobutyrophenone and it has the following structural formula: Haloperidol, USP is a white or slightly yellowish crystalline powder.
Boxed warning
Increased Mortality in Elderly Patients with Dementia-Related Psychosis Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of seventeen place.
Causality screen of the 40 strongest signals
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, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,144 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Myocardial reperfusion injury | 16 | 746.5 380.7–1,463.7ROR 747.0 · calibrated p 3e-13 ✓ | 268.7 EB05 175.4 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Paroxysmal perceptual alteration | 27 | 687.1 413.2–1,142.5ROR 687.9 · calibrated p 7e-14 ✓ | 298.4 EB05 215.3 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=27 · 100% clinician | no trial data cached |
| Encephalitis toxic | 19 | 261.6 156.3–437.7ROR 261.8 · calibrated p 4e-10 ✓ | 166.6 EB05 112.7 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=19 | no trial data cached |
| Antipsychotic drug level below therapeutic | 158 | 251.3 210.5–300.0ROR 252.9 · calibrated p 6e-11 ✓ | 189.2 EB05 165.7 · IC025 +6.6 3/3 methods agree | Lab value / disease marker | serious n=158 · ♀ 7% (drug 44%) · 90% clinician | no trial data cached |
| Malignant catatonia | 57 | 241.8 180.1–324.5ROR 242.3 · calibrated p 2e-10 ✓ | 176.9 EB05 141.6 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=57 · 100% clinician | no trial data cached |
| Delusion of grandeur | 80 | 185.6 145.7–236.4ROR 186.2 · calibrated p 1e-9 ✓ | 146.9 EB05 121.8 · IC025 +5.9 3/3 methods agree | Not in label — unassessed | serious n=80 · ♀ 0% (drug 44%) · 95% clinician | no trial data cached |
| Refusal of examination | 21 | 161.8 101.4–258.1ROR 161.9 · calibrated p 1e-8 ✓ | 121.1 EB05 83.6 · IC025 +4.3 3/3 methods agree | Reporting / coding artifact | serious n=21 · 100% clinician | no trial data cached |
| Spasmodic dysphonia | 46 | 157.7 115.1–216.0ROR 158.0 · calibrated p 7e-9 ✓ | 126.1 EB05 98.3 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious n=46 · ♀ 0% (drug 44%) · 100% clinician | no trial data cached |
| Neuroleptic malignant syndrome | 1,661 | 138.5 131.6–145.6ROR 148.4 · calibrated p 5e-9 ✓ | 118.8 EB05 114.1 · IC025 +6.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 73.3 · 93% clinician | no trial data cached |
| Waxy flexibility | 23 | 127.9 82.5–198.3ROR 128.0 · calibrated p 7e-8 ✓ | 102.0 EB05 71.6 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=23 · 100% clinician | no trial data cached |
| Cogwheel rigidity | 105 | 94.3 77.1–115.3ROR 94.7 · calibrated p 2e-7 ✓ | 83.6 EB05 71.0 · IC025 +5.6 3/3 methods agree | Labeled adverse reaction exact term | serious n=100 · 96% clinician | no trial data cached |
| Disinhibition | 153 | 89.4 75.7–105.5ROR 89.9 · calibrated p 3e-7 ✓ | 80.1 EB05 70.0 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=151 · ♀ 0% (drug 44%) | no trial data cached |
| Catatonia | 448 | 80.0 72.7–88.1ROR 81.5 · calibrated p 5e-7 ✓ | 73.0 EB05 67.5 · IC025 +5.9 3/3 methods agree | Not in label — unassessed | serious n=437 · 94% clinician | no trial data cached |
| Echolalia | 25 | 72.1 48.0–108.5ROR 72.2 · calibrated p 3e-6 ✓ | 63.4 EB05 45.2 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=25 · ♀ 67% (drug 44%) | no trial data cached |
| Colonic pseudo-obstruction | 20 | 64.8 41.2–102.2ROR 64.9 · calibrated p 7e-6 ✓ | 57.2 EB05 39.1 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=20 | no trial data cached |
| Oscillopsia | 18 | 63.2 39.2–102.1ROR 63.3 · calibrated p 9e-6 ✓ | 55.6 EB05 37.2 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=18 | no trial data cached |
| Oromandibular dystonia | 49 | 62.1 46.4–82.9ROR 62.2 · calibrated p 5e-6 ✓ | 56.7 EB05 44.5 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=46 · 92% clinician | no trial data cached |
| Anticholinergic syndrome | 106 | 60.7 49.8–73.9ROR 60.9 · calibrated p 5e-6 ✓ | 56.1 EB05 47.7 · IC025 +5.2 3/3 methods agree | Labeled (related wording) related wording | serious n=106 | no trial data cached |
| Neglect of personal appearance | 16 | 59.7 36.0–99.1ROR 59.8 · calibrated p 1e-5 ✓ | 52.5 EB05 34.3 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=15 | no trial data cached |
| Breathing-related sleep disorder | 15 | 56.7 33.6–95.7ROR 56.8 · calibrated p 2e-5 ✓ | 50.0 EB05 32.2 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=15 | no trial data cached |
| Grandiosity | 21 | 52.2 33.6–81.1ROR 52.2 · calibrated p 2e-5 ✓ | 47.2 EB05 32.6 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=21 · 100% clinician | no trial data cached |
| Visceral congestion | 28 | 51.1 34.9–74.8ROR 51.2 · calibrated p 2e-5 ✓ | 46.8 EB05 34.0 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=28 · ♀ 0% (drug 44%) · 100% clinician | no trial data cached |
| Psychotic symptom | 114 | 50.4 41.7–60.9ROR 50.6 · calibrated p 1e-5 ✓ | 47.3 EB05 40.4 · IC025 +5.0 3/3 methods agree | Labeled (related wording) related wording | serious n=113 · 94% clinician | no trial data cached |
| Resting tremor | 36 | 50.0 35.7–69.9ROR 50.0 · calibrated p 2e-5 ✓ | 46.1 EB05 34.8 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=36 · ♀ 21% (drug 44%) | no trial data cached |
| Schizophrenia, paranoid type | 20 | 49.4 31.5–77.5ROR 49.4 · calibrated p 4e-5 ✓ | 44.9 EB05 30.7 · IC025 +3.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=20 | no trial data cached |
| Protrusion tongue | 31 | 48.2 33.6–69.2ROR 48.3 · calibrated p 3e-5 ✓ | 44.5 EB05 32.8 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=28 | no trial data cached |
| Drug-genetic interaction | 17 | 46.5 28.5–75.8ROR 46.5 · calibrated p 6e-5 ✓ | 42.2 EB05 27.9 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=17 | no trial data cached |
| Oculogyric crisis | 108 | 46.0 37.9–55.9ROR 46.2 · calibrated p 3e-5 ✓ | 43.4 EB05 36.9 · IC025 +4.9 3/3 methods agree | Labeled adverse reaction exact term | serious n=104 | no trial data cached |
| Water intoxication | 26 | 45.7 30.8–67.8ROR 45.7 · calibrated p 5e-5 ✓ | 42.1 EB05 30.2 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=26 | no trial data cached |
| Extrapyramidal disorder | 1,255 | 44.8 42.4–47.4ROR 47.2 · calibrated p 2e-5 ✓ | 42.6 EB05 40.7 · IC025 +5.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 28.0 · 94% clinician | no trial data cached |
| Sexually inappropriate behaviour | 22 | 42.8 27.9–65.6ROR 42.8 · calibrated p 7e-5 ✓ | 39.5 EB05 27.5 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=21 · 100% clinician | no trial data cached |
| Schizoaffective disorder | 85 | 42.4 34.1–52.7ROR 42.5 · calibrated p 4e-5 ✓ | 40.0 EB05 33.4 · IC025 +4.7 3/3 methods agree | Labeled adverse reaction exact term | serious n=82 | no trial data cached |
| Emotional poverty | 82 | 41.8 33.5–52.1ROR 41.9 · calibrated p 5e-5 ✓ | 39.5 EB05 32.8 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=81 · ♀ 0% (drug 44%) | no trial data cached |
| Lymphocyte count abnormal | 52 | 41.1 31.1–54.3ROR 41.2 · calibrated p 6e-5 ✓ | 38.7 EB05 30.7 · IC025 +4.4 3/3 methods agree | Lab value / disease marker | serious n=52 · ♀ 0% (drug 44%) · 90% clinician | no trial data cached |
| Akathisia (inner restlessness) | 625 | 40.9 37.7–44.2ROR 41.9 · calibrated p 4e-5 ✓ | 39.0 EB05 36.5 · IC025 +5.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 32.8 | no trial data cached |
| Mutism | 66 | 40.8 31.8–52.2ROR 40.9 · calibrated p 6e-5 ✓ | 38.5 EB05 31.3 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=66 · 100% clinician | no trial data cached |
| Parkinsonian gait | 28 | 40.1 27.5–58.6ROR 40.2 · calibrated p 9e-5 ✓ | 37.5 EB05 27.2 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=28 | no trial data cached |
| Blunted affect | 31 | 38.1 26.6–54.5ROR 38.1 · calibrated p 1e-4 ✓ | 35.7 EB05 26.4 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=31 | no trial data cached |
| Schizophrenia | 516 | 37.7 34.6–41.2ROR 38.5 · calibrated p 7e-5 ✓ | 36.1 EB05 33.6 · IC025 +5.0 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 22.9 | no trial data cached |
| Parkinsonism | 410 | 37.4 33.9–41.2ROR 38.0 · calibrated p 7e-5 ✓ | 35.8 EB05 33.0 · IC025 +4.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 24.5 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
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 |
|---|---|---|---|---|---|---|
| Drug ineffective (drug did not work) | 2,164 | 1.4 1.3–1.5ROR 1.4 · calibrated p 0.602 | 1.4 EB05 1.4 · IC025 +0.4 | Reporting / coding artifact | serious PRR 2.3 | no trial data cached |
| Drug interaction | 1,713 | 9.3 8.9–9.7ROR 9.9 · calibrated p 0.033 ✓ | 9.2 EB05 8.8 · IC025 +3.1 3/3 methods agree | Reporting / coding artifact | serious PRR 6.3 · 93% clinician | no trial data cached |
| Neuroleptic malignant syndrome | 1,661 | 138.5 131.6–145.6ROR 148.4 · calibrated p 5e-9 ✓ | 118.8 EB05 114.1 · IC025 +6.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 73.3 · 93% clinician | no trial data cached |
| Off label use (used outside approved label) | 1,426 | 1.4 1.3–1.5ROR 1.4 · calibrated p 0.592 | 1.4 EB05 1.3 · IC025 +0.4 | Reporting / coding artifact | serious PRR 1.5 | no trial data cached |
| Extrapyramidal disorder | 1,255 | 44.8 42.4–47.4ROR 47.2 · calibrated p 2e-5 ✓ | 42.6 EB05 40.7 · IC025 +5.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 28.0 · 94% clinician | no trial data cached |
| Weight increased (weight gain) | 1,228 | 4.7 4.5–5.0ROR 4.9 · calibrated p 0.244 | 4.7 EB05 4.5 · IC025 +2.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.2 | no trial data cached |
| Toxicity to various agents | 1,113 | 5.7 5.4–6.0ROR 5.9 · calibrated p 0.157 | 5.6 EB05 5.4 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 3.6 · 95% clinician | no trial data cached |
| Agitation | 889 | 10.4 9.7–11.1ROR 10.8 · calibrated p 0.025 ✓ | 10.3 EB05 9.7 · IC025 +3.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.1 | no trial data cached |
| Somnolence (drowsiness) | 842 | 3.6 3.3–3.8ROR 3.7 · calibrated p 0.445 | 3.6 EB05 3.4 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.6 | no trial data cached |
| Pyrexia (fever) | 824 | 2.0 1.9–2.2ROR 2.1 · calibrated p 0.980 | 2.0 EB05 1.9 · IC025 +0.9 | Labeled adverse reaction exact term | serious PRR 1.5 | no trial data cached |
| Condition aggravated | 821 | 2.3 2.2–2.5ROR 2.4 · calibrated p 0.872 | 2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree | Reporting / coding artifact | serious PRR 2.1 · 91% clinician | no trial data cached |
| Delirium | 788 | 19.9 18.5–21.3ROR 20.5 · calibrated p 0.002 ✓ | 19.4 EB05 18.3 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 12.1 · 91% clinician | no trial data cached |
| Confusional state (confusion) | 764 | 4.0 3.8–4.3ROR 4.1 · calibrated p 0.354 | 4.0 EB05 3.8 · IC025 +1.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.1 | no trial data cached |
| Vomiting | 736 | 1.3 1.2–1.4ROR 1.3 · calibrated p 0.541 | 1.3 EB05 1.3 · IC025 +0.3 | Labeled adverse reaction exact term | serious PRR 1.2 | no trial data cached |
| Death | 734 | 0.7 0.7–0.8ROR 0.7 · calibrated p 0.140 | 0.7 EB05 0.7 · IC025 -0.6 PRR-only: not supported by EBGM or IC | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 0.4 | 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.
- Paroxysmal perceptual alteration — n=27, PRR 687.1
- Malignant catatonia — n=57, PRR 241.8
- Delusion of grandeur — n=80, PRR 185.6
- Spasmodic dysphonia — n=46, PRR 157.7
- Waxy flexibility — n=23, PRR 127.9
- Disinhibition — n=153, PRR 89.4
- Catatonia — n=448, PRR 80.0
- Echolalia — n=25, PRR 72.1
- Colonic pseudo-obstruction — n=20, PRR 64.8
- Oromandibular dystonia — n=49, PRR 62.1
✓ A hand-written Bradford Hill causality assessment exists for this drug: Haloperidol ↔ QT prolongation / torsades.
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 Haloperidol Lactate?
In FDA FAERS, the most frequently co-reported reaction terms for Haloperidol Lactate are neuroleptic malignant syndrome, extrapyramidal disorder, weight increased, toxicity to various agents, agitation, somnolence. 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 Haloperidol Lactate have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: Increased Mortality in Elderly Patients with Dementia-Related Psychosis Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of seventeen place.
Do FAERS signals prove that Haloperidol Lactate 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 7d1a9689-23c8-44ef-a474-8c607e13d794, effective 20260602; matched on
openfda.generic_name.exact:"HALOPERIDOL LACTATE") - 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, 1,184 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 2026-10-14. 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.