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Dofetilide Oral capsule

What is this medicine?

DOFETILIDE (doe FET il ide) is an antiarrhythmic drug. It helps make your heart beat regularly. This medicine also helps to slow rapid heartbeats.

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. You can take this medicine with or without food. Do not drink grapefruit juice with this medicine. Take your doses at regular intervals. Do not take your medicine more often than directed. Do not stop taking this medicine suddenly. This may cause serious, heart-related side effects. Your doctor will tell you how much medicine to take. If your doctor wants you to stop the medicine, the dose will be slowly lowered over time to avoid any side effects.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

  • breathing problems

  • dizziness

  • fast or rapid beating of the heart

  • feeling faint or lightheaded

  • swelling of the ankles

  • unusually weak or tired

  • vomiting

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • cough

  • diarrhea

  • difficulty sleeping

  • headache

  • nausea

  • stomach pain

What may interact with this medicine?

Do not take this medicine with any of the following medications:

  • arsenic trioxide

  • certain macrolide antibiotics

  • certain medicines for fungal infections like ketoconazole and itraconazole

  • certain quinolone antibiotics

  • cimetidine

  • cisapride

  • conivaptan

  • cyclobenzaprine

  • droperidol

  • grapefruit juice

  • haloperidol

  • hawthorn

  • imatinib

  • levomethadyl

  • medicines for depression, anxiety, or psychotic disturbances

  • medicines for HIV, AIDS called protease inhibitors

  • medicines for malaria like chloroquine and halofantrine

  • megestrol

  • memantine

  • metformin

  • methadone

  • mibefradil

  • mifepristone

  • other medicines to control heart rhythm

  • pentamidine

  • phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine

  • ranolazine

  • sertindole

  • telithromycin

  • thiazide diuretics

  • trimethoprim

  • trospium

  • vardenafil

  • verapamil

  • ziprasidone

This medicine may also interact with the following medications:

  • antidepressants called SSRIs

  • certain medicines for fungal infections like fluconazole or voriconazole

  • certain heart medicines like digoxin or diltiazem

  • diuretics

  • dronabinol, THC

  • norfloxacin

  • quinine

  • zafirlukast

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect the medicine from moisture or humidity. Keep container tightly closed. Throw away any unused medicine after the expiration date.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • heart disease or heart failure

  • history of low levels of potassium or magnesium

  • kidney disease

  • liver disease

  • an unusual or allergic reaction to dofetilide, other medicines, foods, dyes, or preservatives

  • pregnant or trying to get pregnant

  • breast-feeding

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular checks on your progress. Wear a medical ID bracelet or chain, and carry a card that describes your disease and details of your medicine and dosage times.

Check your heart rate and blood pressure regularly while you are taking this medicine. Ask your doctor or health care professional what your heart rate and blood pressure should be, and when you should contact him or her. Your doctor or health care professional also may schedule regular tests to check your progress.

You will be started on this medicine in a specialized facility for at least three days. You will be monitored to find the right dose of medicine for you. It is very important that you take your medicine exactly as prescribed when you leave the hospital. The correct dosing of this medicine is very important to treat your condition and prevent possible serious side effects.