Haloperidol Decanoate side effects: what 1,721 FDA adverse event reports show

Haloperidol Decanoate · 172 reaction terms · 4,877 drug–reaction co-reports · data 2026-09-14

Drug class

Typical antipsychotic

FDA label, Indications wording

Who reports

1,721 reports · 89% serious · 150 with death outcome · 39% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Haloperidol Decanoate Injection is indicated for the treatment of schizophrenia in adults who were previously taking a stable dosage of an immediate-release oral haloperidol product. Haloperidol Decanoate Injection is a typical antipsychotic indicated for the treatment of schizophrenia in adults who were previously taking a stable dosage of an immediate-release oral haloperidol product ( 1 ).

FDA label, Indications and Usage

What it is

Haloperidol Decanoate Injection is the decanoate ester of haloperidol, for intramuscular use. Haloperidol is a typical antipsychotic.

FDA label, Description section

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. Haloperidol decanoate injection is not approved for the treatment of patients with dementia-related psychosis [see Warnings and Precautions (5.1) ] .

FDA 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 — boxed warning 6Labeled adverse reaction 12Likely indication confounding 1Reporting / coding artifact 4Outcome field, not a reaction 1Not in label — unassessed 16

What the badges mean

Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
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.
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.
Outcome field, not a reaction Death is a report outcome, not a reaction term. It is dominated by the underlying illness; see the seriousness profile and the boxed warning instead.
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. 132 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.

Show: hide coding/lab/outcome terms hide indication terms unlabeled only hide PRR-only

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Akathisia (inner restlessness)	141	80.0 68.1–94.1ROR 84.3 · χ² 10,817 / p <1e-300	78.4 EB05 68.1 · IC025 +5.7 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 96.7 · ♀ 17% (drug 39%)	no trial data cached
Neuroleptic malignant syndrome	112	72.9 60.7–87.5ROR 76.0 · χ² 7,799 / p <1e-300	71.4 EB05 60.9 · IC025 +5.5 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 63.5 · 97% clinician	no trial data cached
Extrapyramidal disorder	182	56.0 48.7–64.5ROR 60.0 · χ² 9,721 / p <1e-300	55.3 EB05 48.9 · IC025 +5.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 48.8 · 97% clinician	no trial data cached
Euphoric mood	70	52.4 41.6–66.1ROR 53.8 · χ² 3,458 / p <1e-300	51.4 EB05 42.1 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=66 · ♀ 0% (drug 39%) · 92% clinician	no trial data cached
Schizophrenia	72	45.7 36.3–57.4ROR 46.9 · χ² 3,083 / p <1e-300	44.9 EB05 36.8 · IC025 +4.7 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 33.1	no trial data cached
Parkinsonism	50	39.5 30.0–52.0ROR 40.2 · χ² 1,830 / p <1e-300	38.8 EB05 30.6 · IC025 +4.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 40.4	no trial data cached
Salivary hypersecretion	42	32.4 24.0–43.7ROR 32.9 · χ² 1,241 / p 5e-272	31.8 EB05 24.5 · IC025 +4.0 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 29.0 · 97% clinician	no trial data cached
Obesity	66	31.8 25.1–40.4ROR 32.6 · χ² 1,934 / p <1e-300	31.5 EB05 25.6 · IC025 +4.3 3/3 methods agree	Not in label — unassessed	serious PRR 32.8 · ♀ 2% (drug 39%)	no trial data cached
Increased appetite	72	29.5 23.5–37.0ROR 30.2 · χ² 1,947 / p <1e-300	29.2 EB05 23.9 · IC025 +4.2 3/3 methods agree	Not in label — unassessed	serious PRR 72.1 · ♀ 0% (drug 39%) · 92% clinician	no trial data cached
Muscle rigidity	41	26.4 19.5–35.8ROR 26.8 · χ² 973 / p 5e-214	26.0 EB05 20.0 · IC025 +3.8 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 16.4 · 92% clinician	no trial data cached
Leukaemia	31	25.3 17.8–35.9ROR 25.6 · χ² 697 / p 7e-154	24.9 EB05 18.3 · IC025 +3.6 3/3 methods agree	Not in label — unassessed	serious PRR 26.2 · ♀ 0% (drug 39%) · 93% clinician	no trial data cached
Hallucination, auditory	49	23.7 17.9–31.3ROR 24.1 · χ² 1,039 / p 3e-228	23.4 EB05 18.4 · IC025 +3.8 3/3 methods agree	Not in label — unassessed	serious PRR 17.8 · 90% clinician	no trial data cached
Sedation	79	23.3 18.7–29.0ROR 24.0 · χ² 1,661 / p <1e-300	23.1 EB05 19.1 · IC025 +4.0 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 19.3 · ♀ 18% (drug 39%)	no trial data cached
Dystonia	58	22.9 17.8–29.6ROR 23.4 · χ² 1,191 / p 3e-261	22.7 EB05 18.2 · IC025 +3.8 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 21.1 · ♀ 11% (drug 39%)	no trial data cached
Prescribed overdose	53	21.1 16.1–27.5ROR 21.4 · χ² 990 / p 1e-217	20.9 EB05 16.5 · IC025 +3.7 3/3 methods agree	Not in label — unassessed	serious PRR 32.1 · ♀ 2% (drug 39%) · 91% clinician	no trial data cached
Psychotic disorder	77	20.0 16.1–25.0ROR 20.6 · χ² 1,372 / p 1e-300	19.9 EB05 16.4 · IC025 +3.8 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 8.5	no trial data cached
Delusion	40	19.9 14.6–27.0ROR 20.1 · χ² 696 / p 1e-153	19.6 EB05 15.0 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious PRR 14.2 · ♀ 17% (drug 39%)	no trial data cached
Tardive dyskinesia (persistent involuntary movements)	70	18.9 15.0–23.8ROR 19.4 · χ² 1,166 / p 6e-256	18.7 EB05 15.3 · IC025 +3.7 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 15.3	no trial data cached
Leukopenia (low white blood cells)	105	16.2 13.4–19.5ROR 16.8 · χ² 1,479 / p <1e-300	16.1 EB05 13.6 · IC025 +3.6 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 15.8	no trial data cached
Treatment noncompliance	110	15.6 12.9–18.7ROR 16.2 · χ² 1,484 / p <1e-300	15.5 EB05 13.2 · IC025 +3.5 3/3 methods agree	Reporting / coding artifact	serious PRR 15.2	no trial data cached
Suicide attempt	123	15.5 13.1–18.5ROR 16.2 · χ² 1,661 / p <1e-300	15.5 EB05 13.3 · IC025 +3.6 3/3 methods agree	Not in label — unassessed	serious PRR 14.0 · ♀ 14% (drug 39%)	no trial data cached
Sexual dysfunction	23	15.1 10.1–22.7ROR 15.2 · χ² 289 / p 4e-65	14.7 EB05 10.0 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 10.1	no trial data cached
Inappropriate antidiuretic hormone secretion	15	11.3 6.8–18.7ROR 11.4 · χ² 131 / p 1e-30	10.0 EB05 5.9 · IC025 +2.2 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 6.3	no trial data cached
Sudden death	15	10.8 6.5–17.8ROR 10.8 · χ² 123 / p 6e-29	9.4 EB05 5.6 · IC025 +2.2 3/3 methods agree	Outcome field, not a reaction boxed warning mentions mortality	serious PRR 10.4	no trial data cached
Hypothermia	14	10.6 6.3–17.9ROR 10.6 · χ² 112 / p 2e-26	9.1 EB05 5.3 · IC025 +2.1 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 11.1	no trial data cached
Dyskinesia (involuntary movements)	52	9.8 7.5–12.9ROR 10.0 · χ² 404 / p 3e-90	9.4 EB05 7.4 · IC025 +2.7 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 10.4	no trial data cached
Drug resistance	32	9.6 6.8–13.5ROR 9.7 · χ² 237 / p 1e-53	8.9 EB05 6.4 · IC025 +2.5 3/3 methods agree	Reporting / coding artifact	serious PRR 10.7 · ♀ 16% (drug 39%)	no trial data cached
Muscle tightness	20	9.5 6.1–14.7ROR 9.6 · χ² 143 / p 2e-33	8.4 EB05 5.5 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious PRR 17.0	no trial data cached
Weight increased (weight gain)	272	9.4 8.4–10.5ROR 10.3 · χ² 2,045 / p <1e-300	9.3 EB05 8.4 · IC025 +3.0 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 15.6 · 94% clinician	no trial data cached
Aggression	60	9.2 7.1–11.8ROR 9.4 · χ² 430 / p 9e-96	8.8 EB05 7.0 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious PRR 5.7	no trial data cached
Psychomotor hyperactivity	19	8.7 5.6–13.7ROR 8.8 · χ² 123 / p 8e-29	7.7 EB05 5.0 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 12.6	no trial data cached
Agitation	80	8.3 6.7–10.3ROR 8.6 · χ² 510 / p 3e-113	8.1 EB05 6.7 · IC025 +2.6 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 5.4	no trial data cached
Agranulocytosis (severe loss of white cells)	20	8.3 5.4–12.9ROR 8.4 · χ² 121 / p 2e-28	7.3 EB05 4.9 · IC025 +2.1 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 6.0	no trial data cached
Laceration	10	8.0 4.3–14.9ROR 8.1 · χ² 55 / p 7e-14	6.3 EB05 3.5 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious n=1	no trial data cached
Restlessness	38	8.0 5.8–10.9ROR 8.1 · χ² 224 / p 5e-51	7.4 EB05 5.6 · IC025 +2.3 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 5.0	no trial data cached
Abnormal behaviour	41	7.9 5.8–10.7ROR 8.0 · χ² 240 / p 2e-54	7.4 EB05 5.6 · IC025 +2.3 3/3 methods agree	Not in label — unassessed	serious PRR 5.5 · ♀ 18% (drug 39%)	no trial data cached
Electrocardiogram qt prolonged	37	7.9 5.7–10.9ROR 8.0 · χ² 216 / p 4e-49	7.3 EB05 5.5 · IC025 +2.3 3/3 methods agree	Not in label — unassessed	serious PRR 5.1 · ♀ 64% (drug 39%) · 100% clinician	no trial data cached
Incorrect route of product administration	17	7.8 4.8–12.5ROR 7.8 · χ² 93 / p 2e-22	6.7 EB05 4.3 · IC025 +1.9 3/3 methods agree	Reporting / coding artifact	serious PRR 2.8	no trial data cached
Irritability	59	7.5 5.8–9.7ROR 7.7 · χ² 327 / p 2e-73	7.2 EB05 5.7 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	serious PRR 11.4 · ♀ 2% (drug 39%) · 92% clinician	no trial data cached
Therapeutic product effect incomplete	69	7.5 5.9–9.5ROR 7.7 · χ² 382 / p 2e-85	7.2 EB05 5.9 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 14.3 · ♀ 4% (drug 39%) · 91% 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
Weight increased (weight gain)	272	9.4 8.4–10.5ROR 10.3 · χ² 2,045 / p <1e-300	9.3 EB05 8.4 · IC025 +3.0 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 15.6 · 94% clinician	no trial data cached
Extrapyramidal disorder	182	56.0 48.7–64.5ROR 60.0 · χ² 9,721 / p <1e-300	55.3 EB05 48.9 · IC025 +5.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 48.8 · 97% clinician	no trial data cached
Akathisia (inner restlessness)	141	80.0 68.1–94.1ROR 84.3 · χ² 10,817 / p <1e-300	78.4 EB05 68.1 · IC025 +5.7 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 96.7 · ♀ 17% (drug 39%)	no trial data cached
Drug interaction	129	6.2 5.3–7.4ROR 6.5 · χ² 566 / p 2e-125	6.1 EB05 5.3 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 6.3 · 94% clinician	no trial data cached
Suicide attempt	123	15.5 13.1–18.5ROR 16.2 · χ² 1,661 / p <1e-300	15.5 EB05 13.3 · IC025 +3.6 3/3 methods agree	Not in label — unassessed	serious PRR 14.0 · ♀ 14% (drug 39%)	no trial data cached
Neuroleptic malignant syndrome	112	72.9 60.7–87.5ROR 76.0 · χ² 7,799 / p <1e-300	71.4 EB05 60.9 · IC025 +5.5 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 63.5 · 97% clinician	no trial data cached
Treatment noncompliance	110	15.6 12.9–18.7ROR 16.2 · χ² 1,484 / p <1e-300	15.5 EB05 13.2 · IC025 +3.5 3/3 methods agree	Reporting / coding artifact	serious PRR 15.2	no trial data cached
Tremor (shaking)	109	5.0 4.2–6.0ROR 5.2 · χ² 350 / p 2e-78	4.9 EB05 4.2 · IC025 +2.0 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 5.2	no trial data cached
Leukopenia (low white blood cells)	105	16.2 13.4–19.5ROR 16.8 · χ² 1,479 / p <1e-300	16.1 EB05 13.6 · IC025 +3.6 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 15.8	no trial data cached
Toxicity to various agents	101	4.6 3.8–5.6ROR 4.8 · χ² 285 / p 4e-64	4.5 EB05 3.8 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 4.7 · ♀ 14% (drug 39%) · 93% clinician	no trial data cached
Hospitalisation	91	4.6 3.7–5.6ROR 4.7 · χ² 253 / p 3e-57	4.5 EB05 3.8 · IC025 +1.8 3/3 methods agree	Reporting / coding artifact	serious PRR 1.8	no trial data cached
Agitation	80	8.3 6.7–10.3ROR 8.6 · χ² 510 / p 3e-113	8.1 EB05 6.7 · IC025 +2.6 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 5.4	no trial data cached
Sedation	79	23.3 18.7–29.0ROR 24.0 · χ² 1,661 / p <1e-300	23.1 EB05 19.1 · IC025 +4.0 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 19.3 · ♀ 18% (drug 39%)	no trial data cached
Psychotic disorder	77	20.0 16.1–25.0ROR 20.6 · χ² 1,372 / p 1e-300	19.9 EB05 16.4 · IC025 +3.8 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 8.5	no trial data cached
Increased appetite	72	29.5 23.5–37.0ROR 30.2 · χ² 1,947 / p <1e-300	29.2 EB05 23.9 · IC025 +4.2 3/3 methods agree	Not in label — unassessed	serious PRR 72.1 · ♀ 0% (drug 39%) · 92% 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.

Euphoric mood — n=70, PRR 52.4
Obesity — n=66, PRR 31.8
Increased appetite — n=72, PRR 29.5
Leukaemia — n=31, PRR 25.3
Hallucination, auditory — n=49, PRR 23.7
Prescribed overdose — n=53, PRR 21.1
Delusion — n=40, PRR 19.9
Suicide attempt — n=123, PRR 15.5
Sexual dysfunction — n=23, PRR 15.1
Muscle tightness — n=20, PRR 9.5

✓ 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 Decanoate?

In FDA FAERS, the most frequently co-reported reaction terms for Haloperidol Decanoate are weight increased, extrapyramidal disorder, akathisia, suicide attempt, neuroleptic malignant syndrome, tremor. 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 Decanoate 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. Haloperidol decanoate injection is not approved for the treatment of patients with dementia-related psychosis [see Warnings and Precautions (5.1) ] .

Do FAERS signals prove that Haloperidol Decanoate 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 14f40303-9604-4a30-8e86-8abaeb177ce1, effective 20260408; matched on openfda.generic_name.exact:"HALOPERIDOL DECANOATE")
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, field patient.drug.openfda.generic_name.exact, 172 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.