Dofetilide side effects: what 10,443 FDA adverse event reports show
Drug class
Antiarrhythmic
Who reports
10,443 reports · 60% serious · 810 with death outcome · 49% female
Used for
Maintenance of Normal Sinus Rhythm (Delay in AF/AFl Recurrence) Dofetilide capsules are indicated for the maintenance of normal sinus rhythm (delay in time to recurrence of atrial fibrillation/atrial flutter [AF/AFl]) in patients with atrial fibrillation/atrial flutter of greater than one week duration who have been converted to normal sinus rhythm.
What it is
DESCRIPTION Dofetilide is an antiarrhythmic drug with Class III (cardiac action potential duration prolonging) properties.
Boxed warning
To minimize the risk of induced arrhythmia, patients initiated or re-initiated on dofetilide capsules should be placed for a minimum of 3 days in a facility that can provide calculations of creatinine clearance, continuous electrocardiographic monitoring, and cardiac resuscitation.
Causality screen of the 40 strongest signals
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.
- 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 flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 965 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 |
|---|---|---|---|---|---|---|
| Wrong strength | 44 | 309.0 225.0–424.2ROR 310.3 · χ² 11,418 / p <1e-300 | 239.6 EB05 185.9 · IC025 +5.6 3/3 methods agree | Reporting / coding artifact | serious n=27 · 70% consumer | no trial data cached |
| Cardioversion | 55 | 81.8 62.5–107.0ROR 82.2 · χ² 4,137 / p <1e-300 | 76.5 EB05 61.0 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=52 | no trial data cached |
| Cardiac ablation | 63 | 74.1 57.6–95.2ROR 74.5 · χ² 4,308 / p <1e-300 | 70.0 EB05 56.6 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=61 | no trial data cached |
| Electrocardiogram qt corrected interval prolonged | 25 | 65.0 43.7–96.8ROR 65.2 · χ² 1,465 / p <1e-300 | 60.3 EB05 42.9 · IC025 +4.2 3/3 methods agree | Lab value / disease marker | serious n=23 · 100% clinician | no trial data cached |
| Torsade de pointes | 164 | 42.8 36.7–49.9ROR 43.4 · χ² 6,508 / p <1e-300 | 41.7 EB05 36.6 · IC025 +5.0 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 39.6 · 94% clinician | no trial data cached |
| Electrocardiogram qt prolonged | 445 | 25.1 22.9–27.5ROR 26.2 · χ² 10,172 / p <1e-300 | 24.8 EB05 22.9 · IC025 +4.4 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 21.6 | no trial data cached |
| Sinus arrhythmia | 16 | 24.9 15.2–40.8ROR 25.0 · χ² 340 / p 4e-76 | 24.0 EB05 15.6 · IC025 +3.0 3/3 methods agree | Likely indication confounding term in indications | serious n=8 | no trial data cached |
| Atrial flutter | 97 | 24.6 20.1–30.0ROR 24.8 · χ² 2,146 / p <1e-300 | 24.2 EB05 20.4 · IC025 +4.1 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 21.4 | no trial data cached |
| Atrial fibrillation | 1,064 | 22.1 20.9–23.4ROR 24.5 · χ² 21,311 / p <1e-300 | 21.9 EB05 20.8 · IC025 +4.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 19.7 | no trial data cached |
| Ventricular tachycardia | 174 | 21.3 18.4–24.7ROR 21.6 · χ² 3,312 / p <1e-300 | 21.0 EB05 18.5 · IC025 +4.1 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 19.6 | no trial data cached |
| Atrial tachycardia | 21 | 20.2 13.1–31.0ROR 20.2 · χ² 360 / p 1e-80 | 19.6 EB05 13.4 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious n=20 | no trial data cached |
| Implantable defibrillator insertion | 12 | 18.5 10.5–32.6ROR 18.5 · χ² 180 / p 3e-41 | 17.4 EB05 9.8 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Arrhythmia supraventricular | 10 | 18.4 9.9–34.3ROR 18.4 · χ² 146 / p 6e-34 | 16.9 EB05 8.7 · IC025 +2.2 3/3 methods agree | Labeled (related wording) related wording | serious n=9 | no trial data cached |
| Cardiac fibrillation | 13 | 17.9 10.4–30.9ROR 17.9 · χ² 189 / p 3e-43 | 16.9 EB05 9.8 · IC025 +2.5 3/3 methods agree | Labeled (related wording) related wording | serious n=12 | no trial data cached |
| Cardiac pacemaker insertion | 50 | 16.9 12.8–22.4ROR 17.0 · χ² 728 / p 1e-160 | 16.7 EB05 13.1 · IC025 +3.4 3/3 methods agree | Labeled (related wording) related wording | serious n=48 | no trial data cached |
| Supraventricular extrasystoles | 27 | 16.2 11.1–23.6ROR 16.2 · χ² 366 / p 6e-82 | 15.7 EB05 11.1 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=26 | no trial data cached |
| Heart rate abnormal | 37 | 13.5 9.7–18.6ROR 13.5 · χ² 412 / p 8e-92 | 13.1 EB05 9.7 · IC025 +3.0 3/3 methods agree | Lab value / disease marker | serious n=26 | no trial data cached |
| Ventricular fibrillation | 74 | 13.4 10.7–16.9ROR 13.5 · χ² 833 / p 2e-183 | 13.2 EB05 10.8 · IC025 +3.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.7 | no trial data cached |
| Extrasystoles | 46 | 13.3 9.9–17.7ROR 13.3 · χ² 506 / p 3e-112 | 12.9 EB05 9.9 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious n=34 | no trial data cached |
| Heart rate irregular | 137 | 12.2 10.3–14.4ROR 12.3 · χ² 1,386 / p <1e-300 | 12.0 EB05 10.4 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 9.8 | no trial data cached |
| Ventricular extrasystoles | 62 | 12.0 9.4–15.4ROR 12.1 · χ² 613 / p 1e-135 | 11.7 EB05 9.4 · IC025 +3.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 10.6 | no trial data cached |
| Arrhythmia | 268 | 11.4 10.1–12.8ROR 11.6 · χ² 2,516 / p <1e-300 | 11.3 EB05 10.2 · IC025 +3.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 9.0 | no trial data cached |
| International normalised ratio fluctuation | 11 | 10.6 5.9–19.1ROR 10.6 · χ² 86 / p 1e-20 | 8.6 EB05 4.7 · IC025 +1.9 3/3 methods agree | Lab value / disease marker | – | no trial data cached |
| Tachyarrhythmia | 12 | 9.7 5.5–17.1ROR 9.7 · χ² 85 / p 2e-20 | 7.9 EB05 4.5 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious n=9 | no trial data cached |
| Dilatation ventricular | 10 | 9.5 5.1–17.6ROR 9.5 · χ² 67 / p 1e-16 | 7.4 EB05 4.0 · IC025 +1.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=10 | no trial data cached |
| Ischaemic cardiomyopathy | 14 | 9.1 5.4–15.4ROR 9.1 · χ² 93 / p 3e-22 | 7.6 EB05 4.6 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious n=14 | no trial data cached |
| International normalised ratio decreased | 18 | 8.9 5.6–14.1ROR 8.9 · χ² 118 / p 1e-27 | 7.7 EB05 5.0 · IC025 +2.1 3/3 methods agree | Lab value / disease marker | serious n=14 | no trial data cached |
| Cardiac flutter | 27 | 8.4 5.8–12.3ROR 8.4 · χ² 168 / p 1e-38 | 7.6 EB05 5.4 · IC025 +2.2 3/3 methods agree | Labeled (related wording) related wording | serious n=25 | no trial data cached |
| Haemorrhagic anaemia | 18 | 8.1 5.1–12.9ROR 8.1 · χ² 105 / p 6e-25 | 7.0 EB05 4.6 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious n=18 | no trial data cached |
| Creatinine renal clearance decreased | 15 | 7.5 4.5–12.4ROR 7.5 · χ² 78 / p 6e-19 | 6.3 EB05 4.0 · IC025 +1.8 3/3 methods agree | Lab value / disease marker | serious n=14 | no trial data cached |
| Bundle branch block right | 17 | 7.4 4.6–11.9ROR 7.4 · χ² 88 / p 4e-21 | 6.4 EB05 4.1 · IC025 +1.8 3/3 methods agree | Labeled (related wording) related wording | serious n=16 | no trial data cached |
| Ventricular arrhythmia | 13 | 7.2 4.2–12.3ROR 7.2 · χ² 63 / p 1e-15 | 5.9 EB05 3.6 · IC025 +1.6 3/3 methods agree | Labeled — boxed warning exact term | serious n=11 | no trial data cached |
| International normalised ratio abnormal | 12 | 7.0 3.9–12.3ROR 7.0 · χ² 55 / p 5e-14 | 5.7 EB05 3.4 · IC025 +1.5 3/3 methods agree | Lab value / disease marker | serious n=5 | no trial data cached |
| Electrocardiogram abnormal | 27 | 6.9 4.7–10.1ROR 6.9 · χ² 130 / p 2e-30 | 6.2 EB05 4.5 · IC025 +2.0 3/3 methods agree | Lab value / disease marker | serious PRR 5.0 | no trial data cached |
| Blood magnesium decreased | 29 | 6.8 4.7–9.7ROR 6.8 · χ² 136 / p 9e-32 | 6.2 EB05 4.5 · IC025 +2.0 3/3 methods agree | Lab value / disease marker | serious PRR 6.2 | no trial data cached |
| Electrocardiogram st segment elevation | 11 | 6.7 3.7–12.1ROR 6.7 · χ² 47 / p 3e-12 | 5.4 EB05 3.2 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Heart rate decreased | 115 | 6.6 5.5–7.9ROR 6.6 · χ² 536 / p 9e-119 | 6.4 EB05 5.5 · IC025 +2.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.2 | no trial data cached |
| Product prescribing error | 77 | 6.5 5.2–8.2ROR 6.6 · χ² 356 / p 1e-79 | 6.3 EB05 5.2 · IC025 +2.3 3/3 methods agree | Reporting / coding artifact | serious PRR 8.2 | no trial data cached |
| Cardiac operation | 27 | 6.4 4.4–9.3ROR 6.4 · χ² 117 / p 1e-27 | 5.8 EB05 4.2 · IC025 +1.9 3/3 methods agree | Reporting / coding artifact | serious PRR 6.5 · ♀ 22% (drug 49%) | no trial data cached |
| Pulse absent | 15 | 6.3 3.8–10.5ROR 6.3 · χ² 62 / p 2e-15 | 5.4 EB05 3.4 · IC025 +1.6 3/3 methods agree | Lab value / disease marker | serious n=15 | 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 |
|---|---|---|---|---|---|---|
| Atrial fibrillation | 1,064 | 22.1 20.9–23.4ROR 24.5 · χ² 21,311 / p <1e-300 | 21.9 EB05 20.8 · IC025 +4.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 19.7 | no trial data cached |
| Drug ineffective (drug did not work) | 1,031 | 1.6 1.5–1.7ROR 1.6 · χ² 228 / p 6e-52 | 1.6 EB05 1.5 · IC025 +0.5 | Reporting / coding artifact | serious PRR 2.0 | no trial data cached |
| Dyspnoea (shortness of breath) | 613 | 2.2 2.0–2.4ROR 2.3 · χ² 399 / p 4e-89 | 2.2 EB05 2.0 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.1 | no trial data cached |
| Dizziness | 559 | 2.3 2.1–2.4ROR 2.3 · χ² 398 / p 6e-89 | 2.3 EB05 2.1 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.2 | no trial data cached |
| Fatigue (tiredness) | 532 | 1.4 1.3–1.5ROR 1.4 · χ² 56 / p 3e-14 | 1.4 EB05 1.3 · IC025 +0.3 | Labeled (related wording) related wording | serious PRR 1.4 | no trial data cached |
| Death | 485 | 1.1 1.0–1.2ROR 1.1 · χ² 7 / p 0.003 | 1.1 EB05 1.0 · IC025 +0.0 | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 1.1 | no trial data cached |
| Electrocardiogram qt prolonged | 445 | 25.1 22.9–27.5ROR 26.2 · χ² 10,172 / p <1e-300 | 24.8 EB05 22.9 · IC025 +4.4 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 21.6 | no trial data cached |
| Headache | 393 | 1.3 1.1–1.4ROR 1.3 · χ² 21 / p 2e-6 | 1.3 EB05 1.2 · IC025 +0.2 | Labeled adverse reaction exact term | serious PRR 1.2 | no trial data cached |
| Diarrhoea (diarrhea) | 322 | 1.0 0.9–1.1ROR 1.0 · χ² 0 / p 0.475 | 1.0 EB05 0.9 · IC025 -0.2 PRR-only: not supported by EBGM or IC | Labeled adverse reaction exact term | serious PRR 1.0 | no trial data cached |
| Malaise (feeling unwell) | 322 | 1.5 1.3–1.6ROR 1.5 · χ² 49 / p 1e-12 | 1.5 EB05 1.3 · IC025 +0.4 | Not in label — unassessed | serious PRR 1.2 · 73% consumer | no trial data cached |
| Drug interaction | 298 | 3.8 3.4–4.2ROR 3.9 · χ² 609 / p 1e-134 | 3.8 EB05 3.4 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 2.7 | no trial data cached |
| Nausea | 295 | 0.8 0.7–0.8ROR 0.7 · χ² 25 / p 3e-7 | 0.8 EB05 0.7 · IC025 -0.6 PRR-only: not supported by EBGM or IC | Labeled adverse reaction exact term | serious PRR 0.9 | no trial data cached |
| Asthenia (weakness) | 289 | 1.5 1.4–1.7ROR 1.6 · χ² 56 / p 4e-14 | 1.5 EB05 1.4 · IC025 +0.4 | Labeled adverse reaction exact term | serious PRR 1.4 | no trial data cached |
| Heart rate increased | 288 | 5.9 5.2–6.6ROR 6.0 · χ² 1,156 / p 1e-253 | 5.8 EB05 5.2 · IC025 +2.3 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 6.0 · 74% consumer | no trial data cached |
| Arrhythmia | 268 | 11.4 10.1–12.8ROR 11.6 · χ² 2,516 / p <1e-300 | 11.3 EB05 10.2 · IC025 +3.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 9.0 | 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.
- Cardioversion — n=55, PRR 81.8
- Cardiac ablation — n=63, PRR 74.1
- Supraventricular extrasystoles — n=27, PRR 16.2
- Extrasystoles — n=46, PRR 13.3
- Heart rate irregular — n=137, PRR 12.2
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 Dofetilide?
In FDA FAERS, the most frequently co-reported reaction terms for Dofetilide are atrial fibrillation, dyspnoea, dizziness, fatigue, electrocardiogram qt prolonged, headache. 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 Dofetilide have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: To minimize the risk of induced arrhythmia, patients initiated or re-initiated on dofetilide capsules should be placed for a minimum of 3 days in a facility that can provide calculations of creatinine clearance, continuous electrocardiographic monitoring, and cardiac resuscitation.
Do FAERS signals prove that Dofetilide 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 0cb2ef7d-e35b-483b-9985-cfef99d7b96f, effective 20230110; matched on
openfda.generic_name.exact:"DOFETILIDE") - 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, 1,005 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.