NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated July 13, 2026

Dofetilide

Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026

Dofetilide is a pure class III antiarrhythmic that selectively blocks the rapid component of the delayed rectifier potassium current (IKr). It is used for conversion and maintenance of sinus rhythm in atrial fibrillation/flutter. Due to its QT-prolonging properties and risk of torsades de pointes, initiation requires 3 days of in-hospital ECG monitoring. It is only available through the Tikosyn Education Program (T.I.P.S.).

Evidence tier
Moderate
Indexed sources
10 2017–2024
Interactions
0
Category
Prescription
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Publication status

Exploratory record, not a reviewed medical publication.

See the editorial and medical-review policies for the publication gate.

This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.

In short

What the research says.

A quick, data-only summary. The full evidence, dosing, and sources are below.

Dofetilide is a pure class III antiarrhythmic that selectively blocks the rapid component of the delayed rectifier potassium current (IKr). NutriStack rates the supporting evidence as moderate. Common adult dosing is 125–500 mcg twice daily, adjusted by CrCl and QTc response (as prescribed by your physician), though a prescriber sets the actual dose. This profile indexes 10 sources.

What it's good for
  • Effective for conversion and maintenance of sinus rhythm in AF/AFL7
  • No negative inotropic effects (safe in heart failure)1,2
  • Pure class III mechanism (no mixed pharmacology)
  • No increase in mortality in heart failure patients (DIAMOND-HF)6,1
What to watch for
  • QT prolongation and torsades de pointes (~3% risk)
  • Headache
  • Dizziness
  • Baseline QTc >440 ms (>500 ms if ventricular conduction abnormality)6
  • CrCl <20 mL/min

The bottom line

Evidence rating moderate. Most-documented uses: effective for conversion and maintenance of sinus rhythm in af/afl, no negative inotropic effects (safe in heart failure), pure class iii mechanism (no mixed pharmacology). 10 sources indexed (2017–2024), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

Selectively blocks the rapid component of the delayed rectifier potassium current (IKr) without affecting other potassium currents (IKs, IK1) or sodium/calcium channels. Prolongs the effective refractory period in atrial and ventricular tissue. Prolongs QT interval in a dose-dependent and concentration-dependent manner. No significant beta-blocking, alpha-blocking, or negative inotropic activity.

Class
Class III Antiarrhythmic
Dosing

Dosing & protocol.

Common range
125–500 mcg twice daily, adjusted by CrCl and QTc response (as prescribed by your physician)
Recommended form
Oral capsule

Can be taken with or without food; renally eliminated, strict dose adjustment by creatinine clearance is mandatory

Safety

Full safety detail.

Side effects

  • QT prolongation and torsades de pointes (~3% risk)
  • Headache
  • Dizziness
  • Nausea
  • Chest pain
  • Insomnia

Contraindications

  • Baseline QTc >440 ms (>500 ms if ventricular conduction abnormality)6
  • CrCl <20 mL/min
  • Congenital or acquired long QT syndromes
  • Concurrent use with verapamil, cimetidine, trimethoprim, ketoconazole, prochlorperazine, megestrol, or HCTZ (drug interactions that increase dofetilide levels)
  • Hypokalemia or hypomagnesemia (uncorrected)
Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Reviews & position papers

5

Reference material

5
FAQ

Common questions.

Quick answers about Dofetilide, drawn from the data on this page.

What is Dofetilide?

Dofetilide is a pure class III antiarrhythmic that selectively blocks the rapid component of the delayed rectifier potassium current (IKr). It is used for conversion and maintenance of sinus rhythm in atrial fibrillation/flutter. Due to its QT-prolonging properties and risk of torsades de pointes, initiation requires 3 days of in-hospital ECG monitoring. It is only available through the Tikosyn Education Program (T.I.P.S.).

What is Dofetilide used for?

Commonly cited benefits of Dofetilide include: Effective for conversion and maintenance of sinus rhythm in AF/AFL; No negative inotropic effects (safe in heart failure); Pure class III mechanism (no mixed pharmacology); No increase in mortality in heart failure patients (DIAMOND-HF). NutriStack rates the overall evidence as moderate.

What is a typical dose of Dofetilide?

A typical adult dose of Dofetilide is 125–500 mcg twice daily, adjusted by CrCl and QTc response (as prescribed by your physician). The commonly recommended form is Oral capsule. These are general ranges, not personalized advice; confirm the right dose with a clinician.

What are the side effects of Dofetilide?

Reported side effects include qt prolongation and torsades de pointes (~3% risk), headache, dizziness, nausea, chest pain, insomnia. This is educational information; check with a healthcare professional before use.

How strong is the evidence for Dofetilide?

NutriStack rates this as Moderate, meaning several aligned RCTs or one large RCT plus supporting reviews. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.

Use this with your stack

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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.