DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.A product that may interact with this drug is: fingolimod.Many drugs besides dofetilide may affect the heart rhythm (QT prolongation), including amiodarone, pimozide, procainamide, quinidine, sotalol, macrolide antibiotics (such as erythromycin), and certain quinolone antibiotics (such as sparfloxacin), among others. (See also Precautions section.)Other medications can affect the removal of dofetilide from your body, which may affect how dofetilide works. Examples include hydrochlorothiazide, itraconazole, ketoconazole, megestrol, prochlorperazine, trimethoprim, verapamil, among others.Avoid taking cimetidine while being treated with dofetilide. Ask your doctor or pharmacist about other medications for heartburn/upset stomach.

OVERDOSE: If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include dizziness, fainting.

Report Problems to the Food and Drug Administration You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088. Need help identifying pills and medications? Use the pill identifier tool on RxList.