Drug · FAERS side-effect profile with label screen

Disopyramide side effects: what 850 FDA adverse event reports show

Disopyramide Phosphate · 12 reaction terms · 115 drug–reaction co-reports · data 2026-09-14

Drug class

Not stated in label

Label matched

Disopyramide Phosphate (Disopyramide Phosphate)

closest FDA label found for this product string; brand list suppressed because the label is a related product, not an exact match

Who reports

850 reports · 55% serious · 40 with death outcome · 67% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Disopyramide phosphate is indicated for the treatment of documented ventricular arrhythmias, such as sustained ventricular tachycardia, that, in the judgment of the physician, are life-threatening. Because of the proarrhythmic effects of disopyramide phosphate, its use with lesser arrhythmias is generally not recommended. Treatment of patients with asymptomatic ventricular premature contractions should be avoided.

FDA label, Indications and Usage

What it is

DESCRIPTION Disopyramide phosphate is an antiarrhythmic drug available for oral administration in immediate-release capsules containing 100 mg or 150 mg of disopyramide base, present as the phosphate. The base content of the phosphate salt is 77.6%.

FDA label, Description section

Boxed warning

Mortality In the National Heart, Lung and Blood Institute's Cardiac Arrhythmia Suppression Trial (CAST), a long-term, multi-center, randomized, double-blind study in patients with asymptomatic non-life-threatening ve.

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 9 strongest signals

Likely indication confounding 3Reporting / coding artifact 4Not in label — unassessed 2

What the badges mean

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.
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. 3 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
Ventricular tachycardia	11	16.4 9.1–29.5ROR 16.6 · χ² 144 / p 2e-33	15.1 EB05 8.0 · IC025 +2.3 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 17.3	no trial data cached
Heart rate irregular	15	16.3 9.9–26.9ROR 16.6 · χ² 200 / p 9e-46	15.5 EB05 9.4 · IC025 +2.6 3/3 methods agree	Not in label — unassessed	serious PRR 10.4	no trial data cached
Supraventricular tachycardia	6	15.5 7.0–34.4ROR 15.6 · χ² 67 / p 1e-16	11.9 EB05 4.5 · IC025 +1.5 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious PRR 17.0	no trial data cached
Ventricular extrasystoles	6	14.2 6.4–31.6ROR 14.3 · χ² 61 / p 3e-15	10.6 EB05 4.1 · IC025 +1.4 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious PRR 11.0	no trial data cached
Drug effect less than expected	7	12.3 5.9–25.6ROR 12.3 · χ² 62 / p 2e-15	9.2 EB05 4.1 · IC025 +1.5 3/3 methods agree	Reporting / coding artifact	serious n=2	no trial data cached
Product dispensing error	10	11.3 6.1–21.0ROR 11.5 · χ² 84 / p 2e-20	9.3 EB05 4.8 · IC025 +1.8 3/3 methods agree	Reporting / coding artifact	serious n=4	no trial data cached
Electrocardiogram qt prolonged	15	10.3 6.2–17.0ROR 10.5 · χ² 117 / p 2e-27	8.9 EB05 5.4 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 10.9	no trial data cached
Drug ineffective for unapproved indication	23	10.2 6.8–15.2ROR 10.4 · χ² 182 / p 1e-41	9.3 EB05 6.3 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 8.3 · 77% consumer	no trial data cached
Drug effect incomplete	11	7.4 4.1–13.3ROR 7.4 · χ² 54 / p 8e-14	5.9 EB05 3.4 · IC025 +1.5 3/3 methods agree	Reporting / coding artifact	serious PRR 5.5	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
Drug ineffective for unapproved indication	23	10.2 6.8–15.2ROR 10.4 · χ² 182 / p 1e-41	9.3 EB05 6.3 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 8.3 · 77% consumer	no trial data cached
Electrocardiogram qt prolonged	15	10.3 6.2–17.0ROR 10.5 · χ² 117 / p 2e-27	8.9 EB05 5.4 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 10.9	no trial data cached
Heart rate irregular	15	16.3 9.9–26.9ROR 16.6 · χ² 200 / p 9e-46	15.5 EB05 9.4 · IC025 +2.6 3/3 methods agree	Not in label — unassessed	serious PRR 10.4	no trial data cached
Drug effect incomplete	11	7.4 4.1–13.3ROR 7.4 · χ² 54 / p 8e-14	5.9 EB05 3.4 · IC025 +1.5 3/3 methods agree	Reporting / coding artifact	serious PRR 5.5	no trial data cached
Ventricular tachycardia	11	16.4 9.1–29.5ROR 16.6 · χ² 144 / p 2e-33	15.1 EB05 8.0 · IC025 +2.3 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 17.3	no trial data cached
Product dispensing error	10	11.3 6.1–21.0ROR 11.5 · χ² 84 / p 2e-20	9.3 EB05 4.8 · IC025 +1.8 3/3 methods agree	Reporting / coding artifact	serious n=4	no trial data cached
Drug effect less than expected	7	12.3 5.9–25.6ROR 12.3 · χ² 62 / p 2e-15	9.2 EB05 4.1 · IC025 +1.5 3/3 methods agree	Reporting / coding artifact	serious n=2	no trial data cached
Ventricular extrasystoles	6	14.2 6.4–31.6ROR 14.3 · χ² 61 / p 3e-15	10.6 EB05 4.1 · IC025 +1.4 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious PRR 11.0	no trial data cached
Supraventricular tachycardia	6	15.5 7.0–34.4ROR 15.6 · χ² 67 / p 1e-16	11.9 EB05 4.5 · IC025 +1.5 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious PRR 17.0	no trial data cached
Drug dispensing error	4	6.4 2.4–16.9ROR 6.4 · χ² 13 / p 1e-4	4.0 EB05 1.7 · IC025 +0.2	Reporting / coding artifact	–	no trial data cached
Macular degeneration	4	8.3 3.1–22.0ROR 8.3 · χ² 19 / p 7e-6	4.9 EB05 2.0 · IC025 +0.4 3/3 methods agree	Not in label — unassessed	serious PRR 9.3	no trial data cached
Pharmaceutical product complaint	3	2.8 0.9–8.7ROR 2.8 · χ² 2 / p 0.083	2.3 EB05 0.9 · IC025 -0.9 PRR-only: not supported by EBGM or IC	Not in label — unassessed	serious PRR 3.2	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 Disopyramide?

In FDA FAERS, the most frequently co-reported reaction terms for Disopyramide are electrocardiogram qt prolonged, heart rate irregular, ventricular tachycardia, ventricular extrasystoles, supraventricular tachycardia, macular degeneration. 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 Disopyramide have an FDA boxed warning?

Yes. The current FDA label carries a boxed warning: Mortality In the National Heart, Lung and Blood Institute's Cardiac Arrhythmia Suppression Trial (CAST), a long-term, multi-center, randomized, double-blind study in patients with asymptomatic non-life-threatening ve.

Do FAERS signals prove that Disopyramide 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 31e79459-107f-4d69-a163-90014f1c4772, effective 20260318; matched on openfda.generic_name.exact:"DISOPYRAMIDE PHOSPHATE")
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, 12 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.