Generic Name and Formulations:
Dofetilide 125mcg, 250mcg, 500mcg; caps.
Maintenance of normal sinus rhythm in patients with atrial fibrillation or atrial flutter of >1 week duration who were converted to normal sinus rhythm (use only for highly symptomatic patients). Conversion of atrial fibrillation and atrial flutter to normal sinus rhythm.
≥18yrs: see full labeling. Initiate only in appropriate clinical setting.
<18yrs: not recommended.
Class III antiarrhythmic.
Long QT syndromes. Baseline QT interval or QTc >440msec (500msec in ventricular conduction abnormalities). Severe renal impairment (CrCl <20mL/min). Concomitant hydrochlorothiazide, verapamil, trimethoprim, cimetidine, ketoconazole, or other inhibitors of renal cationic secretion (eg, prochlorperazine, megestrol, dolutegravir).
Monitor QTc, renal function (do baseline CrCl) at least every 3 months, and all concomitant drugs (including OTC drugs, herbs, supplements). Paroxysmal atrial fibrillation. Heart rate <50 beats/min. Sick sinus syndrome. 2nd or 3rd degree heart block, unless paced. Renal or severe hepatic impairment. Maintain normal potassium, magnesium levels. Conditions affecting electrolyte levels. Pregnancy (Cat.C). Nursing mothers: not recommended.
See Contraindications. Stop dofetilide for at least 2 days before starting an interacting drug. Drugs that prolong QT interval (eg, phenothiazines, cisapride, bepridil, tricyclic antidepressants, some macrolides and fluoroquinolones): not recommended. Caution with drugs that undergo renal cationic secretion (eg, triamterene, metformin, amiloride) and with CYP3A4 inhibitors (eg, macrolides, azole antifungals, protease inhibitors, SSRIs, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazodone, norfloxacin, quinine, zafirlukast); these may increase dofetilide levels. Allow at least 3 half-lives to elapse and monitor when withdrawing Class I or III antiarrhythmics before giving 1st dose of dofetilide (see full labeling); reduce serum amiodarone levels to <0.3mg/L or withdraw at least 3 months before starting dofetilide. Potassium-depleting diuretics, digoxin may increase risk of torsade de pointes.
Headache, chest pain, dizziness, respiratory tract infection, dyspnea, nausea, flu syndrome, insomnia, back pain, diarrhea, rash, abdominal pain, torsade de pointes (esp. in females), serious ventricular arrhythmias, sudden death, conduction disturbances.
This product is being made available only to those hospitals and prescribers who have received appropriate education from the manufacturer.