Flecainide (Tambocor)

Why Does My Child Need This Medication and How Does It Work?

  • This medication is used to prevent or treat fast or irregular heart rhythms.
  • This drug works directly on the heart tissue and will slow the nerve impulses in the heart. This helps keep the heart rhythm normal.
  • A normal rhythm improves the blood and oxygen supply to the body.

How Should Flecainide Be Taken?

  • Flecainide is taken three times a day (every eight hours) or two times a day (every 12 hours) depending on the patient.
  • Give at the same time(s) each day to keep a steady level in the bloodstream.
  • The exact amount of medication your child takes is determined by their heart rhythm response to the medication.
  • Over time, medication may need to be increased as your child grows.
  • Flecainide is available at Cincinnati Children’s in a liquid form with a concentration 10 mg / mL. It is available at pharmacies in 50 mg, 100 mg and 150 mg tablets. You can only get the liquid medication from a pharmacy that is capable of making the liquid medication. Your medical team will work with you to find a pharmacy that can prepare a quality formulation for your child.
    • If using the liquid form, shake well immediately before using. Draw up the correct amount in the oral syringe. Use the smallest oral syringe that allows you to give one full dose.
    • When receiving a new supply, always double check the liquid concentration (milligrams / milliliter), dose (milligram) and volume (milliliters). If any of these are different from your last refill, talk with your child’s doctor or pharmacist.

What Else Do I Need to Know When Giving This Medication to My Child?

  • Keep in a safe place, out of the reach of children and animals.
  • When more than one caregiver is giving flecainide doses, create a check-off chart to share between care providers giving the medication to prevent repeated or missed doses.

What Are the Possible Side Effects of This Medication?

Possible side effects:

  • Nausea and or vomiting
  • Diarrhea
  • Pale stools
  • Headache
  • Dizziness or lightheadedness
  • Nervousness

Side effects that need immediate attention:

  • Shortness of breath
  • Chest pain or tightness
  • Palpitations or heart racing
  • Dizziness or fainting
  • Severe headache, nausea, vomiting or diarrhea
  • Swelling of hands or feet
  • Change in eyesight
  • Rash
  • Yellowing of the skin and/or eyes

What If My Child Misses a Dose of This Medication?

  • If a dose is missed, give the missed dose as soon as you remember and adjust the medication schedule as directed. The minimum time between doses is seven hours.
  • Do not give two doses at the same time. Do not give extra doses if you are not sure a dose was received.
  • If your child vomits after a dose, do not give it again.
  • Call the cardiology clinic if your child misses or vomits two doses in a row.
  • Do not ever change the dose or stop giving the medication unless told to do so by the cardiology doctor.

Is It OK to Take with Other Medications?

  • Some medications may affect the amount of flecainide in your child’s blood.
  • Always let your child’s cardiology doctor know before taking any new medication including over-the-counter (OTC), natural products, or vitamins. Sometimes these medications can be avoided, but if that is not possible, the dose of flecainide may have to be changed.

What Safety Measures Do I Need to Take?

  • Do not run out of this medication. Call the pharmacy at least three days before refill is needed.
  • Do not suddenly stop giving this medicine without checking with your doctor. It may result in a serious change in your child’s heart rhythm.
  • Always keep an updated list of all your child's medications (prescription, natural products, vitamins, OTC) with you. Give this list to your child's doctor.
  • Tell your child’s doctor, dentist, or the emergency room about any medicines your child is taking.

When Do I Need to Call My Child's Cardiology Doctor?

Call 911 right away if:

  • You think there has been an overdose. Call 911, then call the cardiology fellow on-call at 513-636-4200. Be ready to tell or show what was taken, how much, and when it happened.
  • Your child shows signs of a very bad reaction. These include wheezing; trouble breathing; fever; itching; bad cough; blue skin color; seizures; swelling of face, lips, tongue, or throat; or if your child is not acting normal.

Call the cardiology doctor if your child:

  • Has chest pain or pressure or a fast heartbeat
  • Has very bad dizziness or passing out
  • Has a very bad headache
  • Gets a rash
  • Does not get better with the medicine or if you believe your child’s health problem is worse

Contact Us

If you have any questions about this medication, contact:

Cincinnati Children’s Hospital Medical Center, The Heart Institute

  • For non-urgent questions: Call the electrophysiology coordinator at 513-391-7756.
  • For emergencies: Call 911. Then call 513-636-4200 and ask to speak with the on-call cardiology fellow.

Last Updated 11/2018