II. Indications

III. Contraindications

  1. QTc Prolongation >440 msec
  2. Creatinine Clearance <20 ml/min
  3. Electrolyte abnormalities (Serum Potassium, Serum Magnesium)
    1. Correct levels prior to starting dose
  4. Concurrent use of medications that increase Dofetilide levels (see Drug Interactions below)

IV. Precautions

  1. Proarrhythmic
    1. Initiate in hospital with telemetry monitoring

V. Mechanism

  1. Sulfonamide
  2. Class III Antiarrhythmic
    1. Prolongs Cardiac Action Potential duration and refractory period (via delayed repolarization)
    2. Does not affect conduction velocity
  3. Potassium Channel Blocker
    1. Selectively blocks cardiac ion channels (rapid component of the delayed rectifier Potassium current)

VI. Dosing

  1. Initiate in hospital with telemetry monitoring (typically 3 days)
    1. Minimum observation after cardioversion 12 hours
  2. Dosing is dependent on Creatinine Clearance and QTc Interval

VII. Safety

  1. Avoid in Lactation
  2. Pregnancy category C

VIII. Drug Interactions

  1. Other medications that prolong QTc Interval
    1. Phenothiazines
    2. Cisapride
    3. Tricyclic Antidepressants
    4. Macrolides
    5. Fluoroquinolones
  2. Medications that increase Dofetilide levels (contraindicated)
    1. Cimetidine
    2. Dolutegravir
    3. Hydrochlorothiazide
    4. Ketoconazole
    5. Megestrol
    6. Prochloroperazine
    7. Trimethoprim
    8. Verapamil

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Related Studies

Cost: Medications

dofetilide (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
DOFETILIDE 125 MCG CAPSULE Generic $0.33 each
DOFETILIDE 250 MCG CAPSULE Generic $0.57 each
DOFETILIDE 500 MCG CAPSULE Generic $0.66 each
tikosyn (on 1/1/2023 at Medicaid.Gov Survey of pharmacy drug pricing)
TIKOSYN 500 MCG CAPSULE Generic $0.66 each

Ontology: dofetilide (C0114771)

Definition (NCI) A sulfonamide class III antiarrhythmic agent and potassium channel blocker. Dofetilide selectively blocks cardiac ion channels of the rapid component of the delayed rectifier potassium current Ikr. This antiarrhythmic agent prolongs cardiac action potential duration and effective refractory period due to delayed repolarization without affecting conduction velocity. This results in a normal sinus rhythm. Dofetilide is used in the treatment of atrial fibrillation and flutter.
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH C063533
SnomedCT 392658005, 116107002
English 1-(4-methanesulfonamidophenoxy)-2-(N-(4-methanesulfonamidophenethyl)-N-methylamine)ethane, 1-MSPMPE, dofetilide, beta-((p-Methanesulfonamidophenethyl)methylamino)methanesulfono-p-phenetidide, dofetilide (medication), dofetilide [Chemical/Ingredient], DOFETILIDE, Methanesulfonamide, N-(4-(2-(methyl(2-(4-((methylsulfonyl)amino)phenoxy)ethyl)amino)ethyl)phenyl)-, Dofetilide (product), Dofetilide (substance), Dofetilide
Spanish dofetilida (producto), dofetilida (sustancia), dofetilida

Ontology: Tikosyn (C0876188)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH C063533
English Tikosyn, tikosyn