What is TIKOSYN?

TIKOSYN® (dofetilide) is a prescription medicine. It affects the rhythm of your heart. It is used to treat irregular heartbeats such as atrial fibrillation (AF) and atrial flutter (AFL). It's only suited for patients who have lots of symptoms. TIKOSYN can be used to help your heart beat normally again and/or to keep it beating that way.

Who should not take TIKOSYN?
Do not take TIKOSYN if you:
  • Have an irregular heartbeat condition called long QT syndrome
  • Have kidney problems or are on kidney dialysis
  • Are allergic to dofetilide in TIKOSYN
  • Take any of these medicines:

Cimetidine (Tagamet®, Tagamet HB®)

Verapamil (Calan®, Calan SR®, Covera-HS®, Isoptin®, Isoptin SR®,
Verelan®, Verelan PM®, Tarka®)

Ketoconazole (Nizoral®, Xolegel®, Extina®)

Trimethoprim alone (Proloprim®, Trimpex®) or the combination of trimethoprim
and sulfamethoxazole (Bactrim®, Septra®, Sulfatrim®)

Prochlorperazine (Compazine®, Compro®)

Megestrol (Megace®)

Dolutegravir (Tivicay®)

Hydrochlorothiazide alone or in combination with other medicines (such as Esidrix®,
Ezide®, Hydrodiuril®, Hydro-Par®, Microzide®, or Oretic®)

Ask your doctor if you are not sure if any of your medicines are the kind listed above.

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The benefits of TIKOSYN

TIKOSYN® (dofetilide) has been prescribed to you because you have many symptoms from atrial fibrillation/atrial flutter (AF/AFL). It may help your heart beat in a normal way. TIKOSYN can be used if you have structural heart disease, congestive heart failure, or have suffered a heart attack.

It is not known if TIKOSYN works and is safe in children younger than 18 years of age.

If I have questions about TIKOSYN, whom should I call?

If you have questions about TIKOSYN, there are a number of things you can do:

  • Contact the doctor who prescribed TIKOSYN
  • Contact your local pharmacist
  • Call our Nurse Hotline at 1-877-TIKOSYN (1-877-845-6796)

What is the most important information I should know about taking TIKOSYN?

TIKOSYN® (dofetilide) can cause serious side effects, including a type of abnormal heartbeat called Torsade de Pointes, which can lead to death.

To establish the right dose of TIKOSYN, treatment with TIKOSYN must be started in a hospital where your heart rate and kidney function will be checked for the first 3 days of treatment. It is important that when you go home, you take the exact dose of TIKOSYN that your doctor prescribed for you.

While you take TIKOSYN, always watch for signs of abnormal heartbeat.

Call your doctor and go to the hospital right away if you:

  • Feel faint
  • Become dizzy
  • Have a fast heartbeat
Possible side effects

Like other medicines, TIKOSYN can cause side effects. These include the dangerous abnormal rhythm mentioned above, as well as others.

The most common side effects of TIKOSYN include:

  • Headache
  • Chest pain
  • Dizziness

Call your doctor right away if you have signs of electrolyte imbalance:

  • Severe diarrhea
  • Unusual sweating
  • Vomiting
  • Not hungry (loss of appetite)
  • Drinking more than normal (increased thirst)

TIKOSYN can cause other side effects. Tell your doctor if you have any side effects that bother you or do not go away. For more information, ask your doctor or pharmacist. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

How should I take TIKOSYN?

You must take TIKOSYN® (dofetilide) exactly as your doctor tells you to. After your hospital stay, you will know what your personal TIKOSYN dose is. Then, it’s important you take that dose every day. Your doctor will tell you more about the best time of day to take TIKOSYN.

  • Always listen to all of your doctor’s instructions about TIKOSYN. Keep these in mind:
    • Do not change your TIKOSYN dose unless your doctor tells you to
    • If you miss a dose, just take the next dose at your regular time. Do not take 2 doses of TIKOSYN
      at the same time
    • Never take an extra dose of TIKOSYN, no matter how you feel
    • If you take too much TIKOSYN:
      • Call your doctor or go to the nearest hospital emergency room right away
      • Take your TIKOSYN capsules with you to show to the doctor or nurse
  • Keep all your appointments for tests. Your doctor may need to check your kidney and heart every 3 months to make sure the dose you are taking is still right for you
  • Take TIKOSYN with or without food
  • Do not stop taking TIKOSYN until your doctor tells you to stop
What to tell your doctor before taking TIKOSYN

Tell your doctor about all of your medical conditions, including if you:

  • Have heart problems
  • Have kidney or liver problems
  • Are pregnant or plan to become pregnant. It is not known if TIKOSYN will harm your unborn baby
  • Are breast-feeding or plan to breast-feed. It is not known if TIKOSYN passes into your breast milk

Tell your doctor especially if you take medicines to treat:

  • Heart problems
  • High blood pressure
  • Depression or other mental problems
  • Asthma
  • Allergies or hay fever
  • Skin problems
  • Infections

TIKOSYN and other medicines may affect each other. This can cause serious side effects.

Ask your doctor if you are not sure about the medicines you take. Tell your doctor about all:

  • Prescription and nonprescription medicines
  • Natural or herbal remedies
  • Dietary supplements
  • Vitamins

Know the medicines you take. Keep a list of them. Show it to your doctor and pharmacist when you get a new medicine. And, tell all of your doctors that you are taking TIKOSYN.

Can I share my TIKOSYN with anyone else?

Your TIKOSYN is just to treat your atrial fibrillation/atrial flutter (AF/AFL).

  • TIKOSYN is prescribed just for your AF or AFL. Do not use it to treat any other condition you may have
  • Do not give it to others