Pimozide side effects: what 471 FDA adverse event reports show

Pimozide · 18 reaction terms · 255 drug–reaction co-reports · data 2026-09-14

Drug class

Typical Antipsychotic

FDA label (Established Pharmacologic Class)

Who reports

471 reports · 93% serious · 79 with death outcome · 42% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Pimozide tablets are indicated for the suppression of motor and phonic tics in patients with Tourette’s Disorder who have failed to respond satisfactorily to standard treatment. Pimozide tablets are not intended as a treatment of first choice nor is it intended for the treatment of tics that are merely annoying or cosmetically troublesome.

FDA label, Indications and Usage

What it is

DESCRIPTION Pimozide, USP is an orally active antipsychotic agent of the diphenyl-butylpiperidine series.

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 17 strongest signals

Labeled adverse reaction 7Labeled (related wording) 2Reporting / coding artifact 4Outcome field, not a reaction 1Not in label — unassessed 3

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.
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. 1 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
Parkinsonism	42	192.6 144.2–257.2ROR 211.3 · χ² 7,783 / p <1e-300	176.5 EB05 136.0 · IC025 +5.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 137.6 · 98% clinician	no trial data cached
Neuroleptic malignant syndrome	29	108.8 76.5–154.9ROR 115.9 · χ² 2,986 / p <1e-300	101.5 EB05 74.1 · IC025 +4.6 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 67.7 · ♀ 19% (drug 42%) · 96% clinician	no trial data cached
Dystonia	28	64.1 44.8–91.9ROR 68.1 · χ² 1,677 / p <1e-300	61.5 EB05 44.6 · IC025 +4.3 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 42.3 · 92% clinician	no trial data cached
Akathisia (inner restlessness)	11	35.9 20.0–64.4ROR 36.7 · χ² 339 / p 5e-76	33.9 EB05 20.2 · IC025 +2.8 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 26.0	no trial data cached
Electrocardiogram qt prolonged	23	28.5 19.1–42.4ROR 29.9 · χ² 583 / p 4e-129	27.9 EB05 19.5 · IC025 +3.5 3/3 methods agree	Labeled (related wording) related wording	serious PRR 17.9 · 95% clinician	no trial data cached
Extrapyramidal disorder	15	26.6 16.2–43.8ROR 27.5 · χ² 345 / p 2e-77	25.8 EB05 16.5 · IC025 +3.0 3/3 methods agree	Labeled (related wording) related wording	serious PRR 18.4	no trial data cached
Intentional self-injury	11	24.3 13.5–43.6ROR 24.8 · χ² 223 / p 1e-50	23.2 EB05 13.5 · IC025 +2.6 3/3 methods agree	Reporting / coding artifact	serious PRR 15.2	no trial data cached
Therapy partial responder	8	23.7 11.9–47.0ROR 24.0 · χ² 152 / p 4e-35	21.9 EB05 10.9 · IC025 +2.1 3/3 methods agree	Reporting / coding artifact	serious PRR 17.8	no trial data cached
Inappropriate antidiuretic hormone secretion	5	21.9 9.1–52.3ROR 22.1 · χ² 80 / p 2e-19	17.7 EB05 5.6 · IC025 +1.4 3/3 methods agree	Not in label — unassessed	serious PRR 13.7	no trial data cached
Tardive dyskinesia (persistent involuntary movements)	12	18.8 10.7–32.8ROR 19.2 · χ² 185 / p 2e-42	17.8 EB05 10.2 · IC025 +2.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 13.9	no trial data cached
Muscle rigidity	5	18.6 7.8–44.6ROR 18.8 · χ² 67 / p 2e-16	14.3 EB05 4.6 · IC025 +1.3 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 13.0	no trial data cached
Serotonin syndrome	8	18.6 9.4–37.0ROR 18.9 · χ² 116 / p 2e-27	16.7 EB05 7.5 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious PRR 11.7	no trial data cached
Intentional drug misuse	6	12.6 5.7–27.9ROR 12.7 · χ² 53 / p 2e-13	9.0 EB05 3.7 · IC025 +1.3 3/3 methods agree	Reporting / coding artifact	serious PRR 14.0	no trial data cached
Sedation	7	12.0 5.7–24.9ROR 12.1 · χ² 60 / p 5e-15	8.9 EB05 4.0 · IC025 +1.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 10.2	no trial data cached
Suicide attempt	15	11.0 6.7–18.1ROR 11.3 · χ² 127 / p 1e-29	9.6 EB05 5.7 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious PRR 6.8	no trial data cached
Foetal exposure during pregnancy	19	10.4 6.7–16.2ROR 10.8 · χ² 153 / p 2e-35	9.3 EB05 6.0 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 6.6	no trial data cached
Completed suicide (death by suicide)	8	4.2 2.1–8.4ROR 4.3 · χ² 17 / p 2e-5	3.5 EB05 2.0 · IC025 +0.6	Outcome field, not a reaction	serious PRR 2.6	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
Parkinsonism	42	192.6 144.2–257.2ROR 211.3 · χ² 7,783 / p <1e-300	176.5 EB05 136.0 · IC025 +5.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 137.6 · 98% clinician	no trial data cached
Neuroleptic malignant syndrome	29	108.8 76.5–154.9ROR 115.9 · χ² 2,986 / p <1e-300	101.5 EB05 74.1 · IC025 +4.6 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 67.7 · ♀ 19% (drug 42%) · 96% clinician	no trial data cached
Dystonia	28	64.1 44.8–91.9ROR 68.1 · χ² 1,677 / p <1e-300	61.5 EB05 44.6 · IC025 +4.3 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 42.3 · 92% clinician	no trial data cached
Electrocardiogram qt prolonged	23	28.5 19.1–42.4ROR 29.9 · χ² 583 / p 4e-129	27.9 EB05 19.5 · IC025 +3.5 3/3 methods agree	Labeled (related wording) related wording	serious PRR 17.9 · 95% clinician	no trial data cached
Foetal exposure during pregnancy	19	10.4 6.7–16.2ROR 10.8 · χ² 153 / p 2e-35	9.3 EB05 6.0 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 6.6	no trial data cached
Suicide attempt	15	11.0 6.7–18.1ROR 11.3 · χ² 127 / p 1e-29	9.6 EB05 5.7 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious PRR 6.8	no trial data cached
Extrapyramidal disorder	15	26.6 16.2–43.8ROR 27.5 · χ² 345 / p 2e-77	25.8 EB05 16.5 · IC025 +3.0 3/3 methods agree	Labeled (related wording) related wording	serious PRR 18.4	no trial data cached
Tardive dyskinesia (persistent involuntary movements)	12	18.8 10.7–32.8ROR 19.2 · χ² 185 / p 2e-42	17.8 EB05 10.2 · IC025 +2.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 13.9	no trial data cached
Intentional self-injury	11	24.3 13.5–43.6ROR 24.8 · χ² 223 / p 1e-50	23.2 EB05 13.5 · IC025 +2.6 3/3 methods agree	Reporting / coding artifact	serious PRR 15.2	no trial data cached
Akathisia (inner restlessness)	11	35.9 20.0–64.4ROR 36.7 · χ² 339 / p 5e-76	33.9 EB05 20.2 · IC025 +2.8 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 26.0	no trial data cached
Completed suicide (death by suicide)	8	4.2 2.1–8.4ROR 4.3 · χ² 17 / p 2e-5	3.5 EB05 2.0 · IC025 +0.6	Outcome field, not a reaction	serious PRR 2.6	no trial data cached
Serotonin syndrome	8	18.6 9.4–37.0ROR 18.9 · χ² 116 / p 2e-27	16.7 EB05 7.5 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious PRR 11.7	no trial data cached
Therapy partial responder	8	23.7 11.9–47.0ROR 24.0 · χ² 152 / p 4e-35	21.9 EB05 10.9 · IC025 +2.1 3/3 methods agree	Reporting / coding artifact	serious PRR 17.8	no trial data cached
Sedation	7	12.0 5.7–24.9ROR 12.1 · χ² 60 / p 5e-15	8.9 EB05 4.0 · IC025 +1.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 10.2	no trial data cached
Intentional drug misuse	6	12.6 5.7–27.9ROR 12.7 · χ² 53 / p 2e-13	9.0 EB05 3.7 · IC025 +1.3 3/3 methods agree	Reporting / coding artifact	serious PRR 14.0	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 Pimozide?

In FDA FAERS, the most frequently co-reported reaction terms for Pimozide are parkinsonism, neuroleptic malignant syndrome, dystonia, electrocardiogram qt prolonged, suicide attempt, extrapyramidal disorder. 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 Pimozide have an FDA boxed warning?

No. The FDA label retrieved for Pimozide has no boxed warning; see the label's Warnings and Precautions for the recognised risks.

Do FAERS signals prove that Pimozide 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 4e954fc2-fdff-486c-beb6-2b8ace717081, effective 20260710; matched on openfda.generic_name.exact:"PIMOZIDE")
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, 18 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.