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Dofetilide

Dofetilide is an antiarrhythmic medicine used to treat atrial fibrillation and atrial flutter by helping restore and maintain a normal heart rhythm.

Brand name Tikosyn
Drug class Antiarrhythmic
Rx Form 1
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026 Content updated Oct 2, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 15 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

✓No current FDA shortage listed · checked Oct 5, 2026
Dofetilide at a glance The quick version — the full detail is in the Patient Information Guide below.
Dr. Brian Staiger, PharmD, BCPS
The Pharmacist’s Take By · Clinical pharmacist · Written

Dofetilide (Tikosyn) is a specialist antiarrhythmic, on the market since about 1999 and available generically, that converts atrial fibrillation or atrial flutter to a normal rhythm and helps keep it there by blocking a potassium channel so heart cells recover more slowly. Most people tolerate it well day to day, noticing headache or dizziness most. Its boxed warning exists because it can itself trigger torsade de pointes, a life-threatening fast rhythm, so it must be started or restarted with at least 3 days of continuous ECG (heart tracing) monitoring in a hospital or similar facility. After that, a suddenly racing heart or fainting means emergency care.

Clinical pearls

  • Cimetidine (Tagamet HB, sold over the counter) and the antibiotic trimethoprim are off-limits, since both sharply raise dofetilide levels.
  • Hydrochlorothiazide, a very common water pill, and verapamil are also contraindicated, so check combination blood pressure products for them.
  • Expect regular checks of kidney function, potassium and magnesium, and call your prescriber about vomiting or diarrhea that could drain potassium.
  • Do not let refills lapse, because restarting after a break means another monitored facility stay to begin again.
How we write & review this content — our editorial policy →
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾

Dofetilide can trigger serious, life-threatening heart rhythm problems. To manage this risk safely, anyone starting or restarting dofetilide must be admitted to a facility — such as a hospital — for a minimum of 3 days. During that time, staff will continuously monitor your heart rhythm on an ECG (electrocardiogram), measure your kidney function to set the right dose, and have equipment and trained personnel on hand in case a dangerous arrhythmia needs to be treated immediately. Do not start or restart dofetilide outside of this monitored setting.

Read the full warning on DailyMed →
How you get itPrescription only
Comes asCapsule
Earliest FDA record1999
Companies listing it with the FDA13
FDA label last updatedApr 21, 2026
FDA’s strongest warning (boxed)Yes, read the warning

Patient information guide A plain-language walkthrough of Dofetilide, written from its FDA label.

What Dofetilide is used for

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Dofetilide capsules are approved to treat atrial fibrillation (AF) and atrial flutter (AFl) — abnormal heart rhythms that can cause palpitations, shortness of breath, and fatigue.

  • Conversion: Dofetilide capsules (including Tikosyn) can convert atrial fibrillation or atrial flutter back to normal sinus rhythm (a regular heartbeat).
  • Maintenance: After normal rhythm is restored, dofetilide capsules (including Tikosyn) help delay the return of atrial fibrillation or atrial flutter in patients who had AF/AFl lasting more than one week.
  • Because of the risk of dangerous arrhythmias, dofetilide is reserved for patients whose AF or AFl causes significant symptoms.
  • Dofetilide capsules have not been shown to be effective for paroxysmal atrial fibrillation (brief episodes that stop on their own).

How Dofetilide works

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Dofetilide is a Class III antiarrhythmic. It works by blocking a specific potassium channel in heart muscle cells — the rapid delayed rectifier potassium channel (IKr). Blocking this channel slows how quickly heart cells electrically recharge after each beat, making it harder for the chaotic, rapid signals of AF or AFl to re-trigger. It does this selectively — it doesn't meaningfully affect sodium channels, blood pressure receptors, or the heart's pumping strength, so it helps correct the rhythm without weakening the heart.

At clinical doses, dofetilide does not affect how fast electrical signals travel through the heart (conduction velocity) or the function of the sinus node (the heart's natural pacemaker). It can terminate certain re-entrant arrhythmias and, in patients with implanted defibrillator devices, it lowers the energy threshold needed to shock the heart back into rhythm.

Dofetilide dosage

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Dofetilide comes as an oral capsule taken twice daily. It can be taken with or without food, and antacids don't affect how it's absorbed. Your exact dose is individually calculated based on your kidney function (creatinine clearance) and the QTc interval measured on your ECG — this is critically important for safety. You must always follow your prescriber's instructions and never adjust the dose yourself.

  • Starting or restarting dofetilide must happen in a hospital or monitored facility for at least 3 days.
  • Kidney function must be measured before the very first dose.
  • Do not stop or restart dofetilide without medical supervision.

Dosing details from the FDA-approved label

From the Dofetilide prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.

In clinical trials, potassium levels were generally maintained above 3.6-4.0 mEq/L.

Read the label’s full dosing text

DOSAGE AND ADMINISTRATION • Therapy with dofetilide capsules must be initiated (and, if necessary, re-initiated) in a setting that provides continuous electrocardiographic (ECG) monitoring and in the presence of personnel trained in the management of serious ventricular arrhythmias. Patients should continue to be monitored in this way for a minimum of three days. Additionally, patients should not be discharged within 12 hours of electrical or pharmacological conversion to normal sinus rhythm. • The dose of dofetilide capsules must be individualized according to calculated creatinine clearance and QTc. (QT interval should be used if the heart rate is <60 beats per minute. There are no data on use of dofetilide capsules when the heart rate is <50 beats per minute.) The usual recommended dose of dofetilide capsules is 500 mcg BID, as modified by the dosing algorithm described below. For consideration of a lower dose, see Special Considerations below. • Serum potassium should be maintained within the normal range before dofetilide capsules treatment is initiated and should be maintained within the normal range while the patient remains on dofetilide capsules therapy. (See WARNINGS, Hypokalemia and Potassium-Depleting Diuretics ). In clinical trials, potassium levels were generally maintained above 3.6-4.0 mEq/L. • Patients with atrial fibrillation should be anticoagulated according to usual medical practice prior to electrical or pharmacological cardioversion. Anticoagulant therapy may be continued after cardioversion according to usual medical practice for the treatment of people with AF. Hypokalemia should be corrected before initiation of dofetilide capsules therapy (see WARNINGS, Ventricular Arrhythmia ). • Patients to be discharged on dofetilide capsules therapy from an inpatient setting as described above must have an adequate supply of dofetilide capsules, at the patient's individualized dose, to allow uninterrupted dosing until the patient can fill a dofetilide capsules prescription. Instructions for Individualized Dose Initiation Initiation of Dofetilide Capsules Therapy Step 1. Electrocardiographic assessment: Prior to administration of the first dose, the QTc or QT must be checked using an average of 5-10 beats.

Excerpted — the section continues on the label. Read the full Dosage and Administration section on DailyMed →

Dofetilide side effects

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The most commonly reported side effects with dofetilide include:

Common side effects

  • Headache
  • Chest pain
  • Dizziness
  • Nausea
  • Shortness of breath (dyspnea)
  • Insomnia (trouble sleeping)
  • Diarrhea
  • Back pain
  • Rash
  • Abdominal pain

When to get medical help

  • Call emergency services immediately if you feel your heart racing, fluttering wildly, or pounding in an unusual or frightening way — this could be a dangerous arrhythmia called Torsade de Pointes.
  • Seek emergency care for fainting, loss of consciousness, or cardiac arrest.
  • Tell your doctor right away if you feel unusually slow heartbeat, significant dizziness, or near-fainting.
  • Contact your doctor promptly if you develop new or worsening shortness of breath or chest pain.
  • Report any signs of stroke such as sudden weakness, facial drooping, or difficulty speaking.

The most serious side effect is Torsade de Pointes (TdP) — a life-threatening fast, irregular heartbeat. If you experience your heart suddenly racing, pounding erratically, feel faint, or lose consciousness, call emergency services immediately. Most TdP events occurred within the first 3 days of treatment, which is why hospital monitoring at the start is required.

Dofetilide warnings and precautions

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  • Risk of dangerous heart arrhythmia (Torsade de Pointes): Dofetilide can cause a potentially fatal abnormal heart rhythm. The risk increases with higher blood levels of the drug, which is why dosing is based on kidney function and ECG monitoring is required at the start.
  • Hospital-only initiation: The first 3 days of treatment (or re-treatment) must take place in a facility with continuous ECG monitoring and cardiac resuscitation capability.
  • Kidney function is critical: As kidney function declines, dofetilide accumulates in the body, raising the risk of arrhythmia. Severe kidney impairment is a contraindication.
  • Low potassium or magnesium raises the risk: These levels must be corrected before and kept normal throughout treatment — especially if you take diuretics.
  • Many drugs are contraindicated: Cimetidine, verapamil, ketoconazole, trimethoprim, and hydrochlorothiazide are among the drugs that must not be taken with dofetilide because they raise blood levels of the drug significantly.
  • Other QT-prolonging drugs: Combining dofetilide with other medicines that also lengthen the QT interval (such as certain antidepressants, antibiotics, and antipsychotics) is not recommended.

Dofetilide interactions

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Dofetilide has several serious drug interactions because many medicines raise its blood levels or amplify its heart effects. Tell every healthcare provider about all medications you take — prescription, over-the-counter, and supplements.

  • Cimetidine (heartburn/ulcer medicine): Contraindicated — raises dofetilide levels by up to 58%; use omeprazole, ranitidine, or antacids as alternatives.
  • Verapamil (calcium channel blocker): Contraindicated — raises peak dofetilide levels and increases TdP risk.
  • Ketoconazole (antifungal): Contraindicated — nearly doubles dofetilide levels, especially in women.
  • Trimethoprim / sulfamethoxazole (antibiotic): Contraindicated — roughly doubles dofetilide levels.
  • Hydrochlorothiazide (HCTZ), alone or with triamterene: Contraindicated — sharply amplifies dofetilide's QT-prolonging effect, partly by lowering potassium.
  • Other QT-prolonging drugs (phenothiazines, tricyclic antidepressants, certain macrolides and fluoroquinolones, cisapride, bepridil): Not recommended in combination.
  • CYP3A4 inhibitors (grapefruit juice, certain antifungals, macrolides, protease inhibitors, diltiazem, amiodarone): Use with caution — can increase dofetilide exposure.
  • Drugs secreted by the same kidney pathway (triamterene, metformin, amiloride): Use with care — may raise dofetilide levels.
  • Digoxin: Concomitant use has been associated with a higher occurrence of TdP; use with awareness and medical oversight.

Interactions listed in the FDA-approved label

From the Dofetilide prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.

  • Cimetidine: Cimetidine 400 mg BID with dofetilide (500 mcg BID) for 7 days increased dofetilide plasma levels by 58%; cimetidine 100 mg BID (OTC dose) increased levels by 13% (500 mcg single dose). Concomitant use is contraindicated. If anti-ulcer therapy is needed, omeprazole, ranitidine, or antacids (aluminum and magnesium hydroxides) are suggested as alternatives.
  • Verapamil: Increased dofetilide peak plasma levels by 42%, although overall exposure was not significantly increased; associated with a higher occurrence of Torsade de Pointes. Concomitant use is contraindicated.
  • Ketoconazole: Ketoconazole 400 mg daily with dofetilide (500 mcg BID) for 7 days increased dofetilide Cmax by 53% in males and 97% in females, and AUC by 41% in males and 69% in females. Concomitant use is contraindicated.
  • Trimethoprim alone or in combination with sulfamethoxazole: Trimethoprim 160 mg with 800 mg sulfamethoxazole BID with dofetilide (500 mcg BID) for 4 days increased dofetilide AUC by 103% and Cmax by 93%. Concomitant use is contraindicated.
  • Hydrochlorothiazide (HCTZ) alone or in combination with triamterene: With HCTZ alone dofetilide AUC increased by 27% and Cmax by 21%, with pharmacodynamic effect increased by 197% (QTc over time) and 95% (maximum QTc); with HCTZ/triamterene AUC increased by 30% and Cmax by 16%, with pharmacodynamic effect increased by 190% and 84%. Concomitant use is contraindicated.
  • Inhibitors of renal cationic secretion; drugs actively secreted by this route (e.g., triamterene, metformin, amiloride): Dofetilide is eliminated in the kidney by cationic secretion; drugs secreted via this route might increase dofetilide levels. Inhibitors of renal cationic secretion are contraindicated; secreted drugs should be co-administered with care.
  • CYP3A4 inhibitors (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast): Dofetilide is metabolized to a small extent by CYP3A4; inhibitors could increase systemic dofetilide exposure. Should be cautiously co-administered with dofetilide.
  • Digoxin: Dofetilide does not affect digoxin pharmacokinetics in healthy volunteers; in patients, concomitant digoxin was associated with a higher occurrence of Torsade de Pointes, and it is not clear whether this is an interaction or due to more severe structural heart disease. No increase in mortality was observed.
  • Amlodipine, phenytoin, glyburide, ranitidine, omeprazole, hormone replacement therapy, antacid (aluminum and magnesium hydroxides), theophylline: In healthy volunteers these did not affect the pharmacokinetics of dofetilide.
  • Warfarin, propranolol, phenytoin, theophylline, oral contraceptives: In healthy volunteers dofetilide does not affect the pharmacokinetics or pharmacodynamics of warfarin, or the pharmacokinetics of propranolol (40 mg twice daily), phenytoin, theophylline, or oral contraceptives.
Read the label’s full interactions text

Drug-Drug Interactions Cimetidine: (see WARNINGS , CONTRAINDICATIONS ) Concomitant use of cimetidine is contraindicated. Cimetidine at 400 mg BID (the usual prescription dose) co-administered with dofetilide (500 mcg BID) for 7 days has been shown to increase dofetilide plasma levels by 58%. Cimetidine at doses of 100 mg BID (OTC dose) resulted in a 13% increase in dofetilide plasma levels (500 mcg single dose). No studies have been conducted at intermediate doses of cimetidine. If a patient requires dofetilide and anti-ulcer therapy, it is suggested that omeprazole, ranitidine, or antacids (aluminum and magnesium hydroxides) be used as alternatives to cimetidine, as these agents have no effect on the pharmacokinetic profile of dofetilide. Verapamil: (see CONTRAINDICATIONS ) Concomitant use of verapamil is contraindicated. Co-administration of dofetilide with verapamil resulted in increases in dofetilide peak plasma levels of 42%, although overall exposure to dofetilide was not significantly increased. In an analysis of the supraventricular arrhythmia and DIAMOND patient populations, the concomitant administration of verapamil with dofetilide was associated with a higher occurrence of Torsade de Pointes. Ketoconazole: (see WARNINGS , CONTRAINDICATIONS ) Concomitant use of ketoconazole is contraindicated. Ketoconazole at 400 mg daily (the maximum approved prescription dose) co-administered with dofetilide (500 mcg BID) for 7 days has been shown to increase dofetilide C max by 53% in males and 97% in females, and AUC by 41% in males and 69% in females. Trimethoprim Alone or in Combination with Sulfamethoxazole: (see WARNINGS , CONTRAINDICATIONS ) Concomitant use of trimethoprim alone or in combination with sulfamethoxazole is contraindicated. Trimethoprim 160 mg in combination with 800 mg sulfamethoxazole co-administered BID with dofetilide (500 mcg BID) for 4 days has been shown to increase dofetilide AUC by 103% and C max by 93%.

Excerpted — the section continues on the label. Read the full Drug Interactions section on DailyMed →

Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.

🌿146 supplements and herbs with documented Dofetilide interactions, ranked by severity Check Dofetilide against a supplement or herb →

Before taking Dofetilide

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  • Tell your doctor if you have congenital or acquired long QT syndrome — dofetilide is contraindicated.
  • Tell your doctor if your baseline QTc interval is elevated (above 440 msec, or 500 msec with certain conduction abnormalities) — this is a contraindication.
  • Tell your doctor about any degree of kidney impairment — severe impairment is a contraindication; moderate impairment requires dose adjustment.
  • Share your full medication list, including OTC medicines and supplements, as many common drugs are contraindicated or require extra caution.
  • Tell your doctor if your potassium or magnesium levels are low — these must be corrected before starting treatment.
  • Tell your doctor if you are pregnant or breastfeeding.
  • Dofetilide must be started in a monitored setting — you cannot begin this medicine at home.

Dofetilide overdose

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There is no specific antidote for a dofetilide overdose. The most likely sign of too much dofetilide is a dangerously prolonged QT interval on the ECG, which can lead to Torsade de Pointes or other serious arrhythmias. If an overdose is suspected, seek emergency care immediately — treatment focuses on continuous heart monitoring and may include intravenous magnesium sulfate or other supportive measures to manage the arrhythmia.

What Dofetilide does in the body

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Dofetilide works by prolonging the time it takes heart cells to electrically recharge after each beat (the action potential duration and effective refractory period), primarily in the atria and ventricles. This shows up on an ECG as a longer QT interval, and the degree of QT prolongation increases in a predictable, dose-dependent way. Despite this electrical effect, dofetilide does not weaken the heart's pumping function — studies found no negative impact on cardiac output, stroke volume, or blood pressure, even in patients with heart failure or reduced ejection fraction. Heart rate was modestly reduced (by about 4–6 beats per minute) in clinical studies.

How your body processes Dofetilide

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Dofetilide is very well absorbed when taken by mouth (more than 90% reaches the bloodstream), and food or antacids do not affect this. Peak blood levels are reached about 2–3 hours after a dose. The drug's half-life is approximately 10 hours, and steady blood levels are reached within 2–3 days of regular dosing. About 80% of the drug is eliminated unchanged through the kidneys, which means kidney function directly affects how much dofetilide accumulates in the body — patients with reduced kidney function have higher drug levels and longer half-lives, making kidney-based dose adjustment essential.

How to store Dofetilide

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Store at 20° to 25°C (68° to 77°F). PROTECT FROM MOISTURE AND HUMIDITY. Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure.

Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

146

Supplements & herbs that interact with Dofetilide

146 supplements and herbal products have documented interactions with Dofetilide in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.

Severity mix
  • Major · 8
  • Moderate · 98
  • Minor · 40
ACTIVATED CHARCOAL Major AMERICAN HELLEBORE Major ARSENIC Major CESIUM Major EPHEDRA Major GRAPEFRUIT Major SIDA CORDIFOLIA Major ST. JOHN'S WORT Major +138 more
Every supplement checked against Dofetilide — ranked by severity The full interaction hub: 8 major · 98 moderate · 40 minor · every one linked to its full report. Check Dofetilide against your exact supplements

Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.

Dofetilide: pharmacist answers to common questions

Quick, plain-English answers to the questions patients ask most about Dofetilide — the kind of thing our pharmacy team would talk through with you at the counter.

Why do I have to go to the hospital just to start this medicine?

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Dofetilide is a powerful heart medicine that, while it helps fix an abnormal rhythm, can — especially in the first few days — cause a dangerous heart rhythm problem called Torsade de Pointes. Your care team needs to watch your heart on a monitor continuously, check your kidney function to get your dose exactly right, and be ready to act quickly if anything unusual happens. Most TdP events happen in those first 3 days, so that monitoring window really does protect you.

How do I know if dofetilide is causing a problem with my heart rhythm?

▾
The warning signs to take seriously are a sudden, very fast or wildly irregular heartbeat, feeling like you might faint, actually fainting, or your heart 'fluttering' in a new or alarming way. If any of those happen, call 911 immediately — don't wait. For milder symptoms like dizziness or chest discomfort, call your doctor right away. That's exactly why the first few days are spent in a monitored setting.

Can I take my usual heartburn or antibiotic medicines while on dofetilide?

▾
Some very common medicines — including cimetidine (Tagamet, even the OTC version), certain antibiotics like trimethoprim, and the antifungal ketoconazole — are completely off-limits while you're on dofetilide because they can dangerously raise its levels in your blood. Before taking any new prescription or over-the-counter medicine, always check with your pharmacist or doctor first. If you need a heartburn medicine, omeprazole or ranitidine are safer alternatives.

Does it matter if my potassium levels are low?

▾
Yes, very much so. Low potassium (or low magnesium) makes dofetilide's risk of causing a dangerous arrhythmia significantly higher. Your levels need to be in the normal range before you start, and kept there the whole time you're on this medicine. If you take a diuretic (water pill) that can lower potassium, your care team will monitor this closely and may ask you to take a potassium supplement.

Will dofetilide definitely keep me in normal heart rhythm?

▾
It's designed to help maintain normal rhythm and delay the return of atrial fibrillation or atrial flutter — but it doesn't guarantee it. Some people do experience a recurrence of their abnormal rhythm even on dofetilide. Your doctor chose this medicine because the benefit is felt to outweigh the risks for your specific situation. Stay consistent with your doses and keep all follow-up appointments so your team can monitor how well it's working.

Can I eat grapefruit or take herbal supplements while on dofetilide?

▾
Grapefruit juice can interfere with the enzyme that helps break down dofetilide, potentially raising its levels in your blood and increasing your risk of side effects. It's best to avoid it. Many herbal supplements and natural products can also interact with heart medicines in unexpected ways, so run everything by your pharmacist before adding anything new — even things that seem harmless.

Is Dofetilide available over the counter?

▾
No. Dofetilide is a prescription medicine: every Dofetilide product listed with the FDA is prescription only, so it is not sold over the counter. Your prescriber decides whether it is appropriate for you, and your pharmacist dispenses it.

When was Dofetilide first available?

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The earliest FDA record we hold for Dofetilide is from 1999: its first approval in Drugs@FDA or its earliest product listing in the NDC Directory, whichever is older. Many older medicines were in use before their first formal FDA approval, so this is the earliest date on record, not necessarily when Dofetilide was first used.

Who makes Dofetilide?

▾
13 companies currently list Dofetilide products in the FDA's NDC Directory, including Accord Healthcare, Inc., Aurobindo Pharma Limited, Bionpharma Inc.. That count includes repackagers and distributors as well as manufacturers (companies that sell only the raw ingredient are not counted), so fewer companies actually make it; the label on your bottle names the one that supplied yours.

Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

More about Dofetilide on HelloPharmacist

📊Dofetilide supplement interactions146 checked — ranked by severity 🌿Drug & Supplement CheckerDofetilide vs. vitamins & herbs 💬Ask a PharmacistFree answer, usually < 24h 🔎NDC & pricing lookupFind Dofetilide NDCs & costs 🅰️Browse Drugs A–ZLook up any medication
Detailed data & references for Dofetilide Forms & strengths, pricing, billing codes, manufacturers, safety reports and sourcing — the data behind the page. Most people can stop here. Each section below opens on a tap.

Dofetilide forms and strengths (how it comes)

Dofetilide is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Capsule

By mouth
Brands Tikosyn
How this form is used
What it may be used for
  • Tikosyn (dofetilide) capsules are used to convert atrial fibrillation or atrial flutter back to a normal heart rhythm.
  • Tikosyn (dofetilide) capsules are used to maintain normal heart rhythm and delay the return of atrial fibrillation or atrial flutter after conversion.
  • Dofetilide capsules (including Dofetilide 0.125mg, 0.25mg, and 0.5mg) are indicated for the same conversion and maintenance uses in atrial fibrillation/atrial flutter.
  • Not shown to be effective for paroxysmal atrial fibrillation (short, self-stopping episodes) across all dofetilide capsule products.
Important instructions
  • Tikosyn must be started — and restarted if therapy is interrupted — only in a setting with continuous ECG monitoring and trained cardiac resuscitation personnel for at least 3 days.
  • Tikosyn dose is individualized based on calculated kidney function (creatinine clearance) and QTc interval measurement; follow your prescriber's instructions exactly.
  • Dofetilide capsules can be taken with or without food — oral bioavailability is not affected by food or antacids.
  • Patients should not be discharged within 12 hours of electrical or pharmacological conversion to normal sinus rhythm, per Tikosyn prescribing guidance.
Available strengths 6 strengths
0.125 mg 125 mcg 0.25 mg 250 mcg 0.5 mg 500 mcg
71 FDA-listed product records ⓘ

Dofetilide on the U.S. market: products, makers and brands

How Dofetilide appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

13 companies list 38 Dofetilide product records with the FDA, mostly as capsule; the earliest marketing or approval year on record is 1999. Brand names on the directory include Tikosyn; the rest are generics.

1
Dose forms ⓘ
13
Labelers (makers, repackagers, distributors)
5
Brand names
38
FDA-listed product records ⓘ
1999
Earliest FDA record ⓘ

Also listed with the FDA, not a patient dose form: Powder (12) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.

Accord Healthcare, Inc.8%
Aurobindo Pharma Limited8%
Bionpharma Inc.8%
Dr. Reddy's Labratories Inc.8%
Exelan Pharmaceuticals, Inc.8%
Granules Pharmaceuticals Inc.8%
Other makers53%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

How widely Dofetilide is used (Medicaid data)

A general measure of how commonly Dofetilide is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.

Think of this as a proxy for how widely Dofetilide is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.

10,363
Medicaid prescriptions filled (Q1–Q4 2025)
$453,466 gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Dofetilide prescribed? Of the 1,601 medications we measure, Dofetilide ranks #926 by Medicaid prescriptions — more than 42% of them.

Where Dofetilide ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5
Total prescriptions — #926 of 1,601
#921 Darunavir 10,563 Rx #922 Tolnaftate 10,552 Rx #923 Pitolisant 10,461 Rx #924 Methylphenidate Transd... 10,420 Rx #925 Dibasic / Monobasic /... 10,418 Rx #926 Dofetilide 10,363 Rx #927 Felodipine 10,352 Rx #928 Sevoflurane 10,339 Rx #929 Menthol / Methyl Salic... 10,307 Rx #930 Ascorbic Acid / Polyet... 10,304 Rx #931 Sotatercept-Csrk 10,198 Rx

Utilization by Dofetilide product

Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.

The 0.5 mg oral capsule is the most-dispensed Dofetilide product — about 44% of these Medicaid prescriptions.

dofetilide 0.5 MG Oral Capsule Most dispensed

4,555 Medicaid prescriptions (Q1–Q4 2025) 44% of Dofetilide prescriptions shown $196,541 gross reimbursement (before rebates) ≈ $43 per prescription (gross)

Summed across the 3 of 28 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 310005

dofetilide 0.25 MG Oral Capsule

4,511 Medicaid prescriptions (Q1–Q4 2025) 44% of Dofetilide prescriptions shown $207,531 gross reimbursement (before rebates) ≈ $46 per prescription (gross)

Summed across the 4 of 30 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 310004

dofetilide 0.125 MG Oral Capsule

1,297 Medicaid prescriptions (Q1–Q4 2025) 13% of Dofetilide prescriptions shown $49,394 gross reimbursement (before rebates) ≈ $38 per prescription (gross)

Summed across the 3 of 28 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 310003

Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.

Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Dofetilide, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 10 of 86 listed Dofetilide NDCs with Medicaid activity.

Compare Dofetilide products

A representative set of FDA-listed product records for Dofetilide — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Showing 38 of 38 products — FDA National Drug Code Directory. See every product, package size and price: browse all 38 Dofetilide NDCs →

Dofetilide recall history

A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.

The FDA’s enforcement reports list 2 Dofetilide recalls since July 2021, covering 4 product listings. None of them is still listed as ongoing. A recall names specific lots from one company, so check the lot number on your own bottle rather than assuming every product is affected; your pharmacist can check whether your supply came from an affected lot.

Class III Jul 18, 2023 · Terminated · SUN PHARMACEUTICAL INDUSTRIES INC
Out of Specification result observed in content uniformity testing
  • Dofetilide Capsules 500 mcg (0.5mg), 60-count bottle, Rx Only, Manufactured by Sun Pharmaceutical Industries Limited, Survey No. 259/15, Dadra-396 191, (U.T of D & NH), India, Distributed by: Sun Pha… Lots: Lot: DNE0217A, Exp 01/2025 FDA record D-1082-2023 →
Class II Feb 7, 2023 · Terminated · Accord Healthcare, Inc.
CGMP Deviations: recalling drug products following an FDA inspection.
  • Dofetilide Capsules 500 mcg (0.5 mg), 60-count bottle, Rx only, Manufactured for: Accord Healthcare, Inc., Durham, NC 27703. Manufactured by: Intas Pharmaceuticals Limited, Pharmez, Ahmedabad-382 213… Lots: Batches: P2101582, P2101661, P2101482, P2101686, Exp. Date 2/28/2023; P2102581, P2102598, Exp. Date 4/30/2023; P2103623, P2103653, P2103670, Exp. Date 5/31/2023; P2104463, P2104385, P2104386, P2104472, P2104709, P2104714, Exp. Date 6/30/20… FDA record D-0385-2023 →
  • Dofetilide Capsules 250 mcg (0.25 mg) 60-count bottle, Rx only, Manufactured for: Accord Healthcare, Inc., Durham, NC 27703. Manufactured by: Intas Pharmaceuticals Limited, Pharmez, Ahmedabad-382 213… Lots: Batches: P2101481 Exp. Date 2/28/2023; P2101985, P2101958, P2102019, Exp. Date 3/31/2023; P2102580, P2102597, Exp. Date 4/30/2023; P2104708, P2104712, Exp. Date 6/30/2023; P2107154, P2107187, Exp. Date 10/31/2023; P2107874, Exp. Date 11/30… FDA record D-0384-2023 →
  • Dofetilide Capsules, 125 mcg (0.125 mg), 60-count bottle, Rx only, Manufactured for: Accord Healthcare, Inc., Durham, NC 27703. Manufactured by: Intas Pharmaceuticals Limited, Pharmez, Ahmedabad-382… Lots: Batches: P2101480, Exp. Date 2/28/2023; P2102579, P2102596, Exp. Date 4/30/2023; P2104711, P2104707, Exp. Date 6/30/2023; P2200771, P2200829, P2200795, Exp. Date 12/31/2023; P2202608, Exp. Date 4/30/2025; P2203492, P2203463, Exp. Date 5/31… FDA record D-0383-2023 →

Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.

RxNorm Concept Web — From Ingredient to Every Form and Strength

This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.

Ingredient (IN) Dofetilide RxCUI 49247 1 dose form · 3 strengths
  1. Dose form (SCDF) Oral Capsule RxCUI 374623 In current FDA listings
    Clinical drug / strength (SCD) 0.125 MG RxCUI 310003 0.25 MG RxCUI 310004 0.5 MG RxCUI 310005

Look up RxCUI 49247 in the RxCUI Atlas →

RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.

💵 What Dofetilide costs pharmacies (NADAC benchmark)

The national average invoice price pharmacies pay for the drug itself, from CMS's NADAC survey (data as of Sep 30, 2026). This is a supply-cost benchmark — not a retail price and not what you'd pay at the counter.

FormStrengthPharmacy acquisition benchmark
Capsule · Oral 0.5 mg $10.66 per capsule NDC details & price history
Capsule · Oral 125 mcg $0.203 per capsule NDC details & price history
Capsule · Oral 250 mcg $0.194 per capsule NDC details & price history
Capsule · Oral 500 mcg $0.193 per capsule NDC details & price history
Why show this? Your out-of-pocket cost depends on insurance, pharmacy markup, and discounts — but the acquisition benchmark tells you whether the medication itself is inexpensive or costly, which strengths cost more per dose, and whether a cash-price quote is in a reasonable range. Each row links to the NDC-level record with its full price history.

Source: CMS National Average Drug Acquisition Cost (NADAC), a survey of retail pharmacy invoice prices. Benchmarks shown are the range across package sizes of a representative product for each form and strength — other manufacturers' products may differ.

Dofetilide brand names

Dofetilide is sold under one brand name in the FDA directory — Tikosyn. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.

Tikosyn

Who makes Dofetilide: manufacturers and labelers

13 companies list Dofetilide products with the FDA. By number of product records, the largest are Accord Healthcare, Inc., Aurobindo Pharma Limited, Bionpharma Inc.. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.

Accord Healthcare, Inc. 3 Aurobindo Pharma Limited 3 Bionpharma Inc. 3 Dr. Reddy's Labratories Inc. 3 Exelan Pharmaceuticals, Inc. 3 Granules Pharmaceuticals Inc. 3 Major Pharmaceuticals 3 NorthStar RxLLC 3 Novadoz Pharmaceuticals LLC 3 Pfizer Laboratories Div Pfizer Inc 3 Sigmapharm Laboratories, LLC 3 Sun Pharmaceutical Industries, Inc. 3 Remedyrepack Inc. 2

Dofetilide drug class (RxNorm)

Dofetilide belongs to the Antiarrhythmic class.

Pharmacologic class Antiarrhythmic
Drug family (ATC) Antiarrhythmics, class III

Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.

Sources for this Dofetilide page

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Apr 21, 2026
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Dofetilide.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Dofetilide after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
15
Finished products in the current FDA directory
38
Companies listing them (makers, repackagers, distributors)
13
FDA labeler codes behind them ⓘ
13
Linked representative label ⓘ
Pfizer Laboratories Div Pfizer Inc
Linked label effective
Apr 21, 2026
Composite sections available
22
Linked SPL Set ID
02438044-d6a3-49e9-a1ac-3aad21ef2c8c
Linked SPL Document ID
0109bfef-980f-4bc8-a802-3d3c45587456
Open the linked representative label on DailyMed ↗

How this page is built

HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Pfizer Laboratories Div Pfizer Inc is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →