Flecainide (Tambocor) for Abnormal heart rhythm

  • Type of Drug: Antiarrhythmic
  • Prescribed for: Abnormal heart rhythm
  • Brand Name: Tambocor

General Information of Flecainide (Tambocor)

Flecainide is prescribed for situations where the abnormal rhythm is so severe as to be life-threatening and does not respond to other drug treatments. Like other antiarrhythmic drugs, Flecainide works by affecting the movement of nervous impulses within the heart.

Flecainide’s effects may not become apparent for 3 to 4 days after you start taking it. Since Flecainide therapy is often started while you are in the hospital, especially if you are being switched from another antiarrhythmic drug to Flecainide, your doctor will be able to closely monitor how well the drug is working for you.

Cautions and Warnings

As with other antiarrhythmic drugs, there is no proof that Flecainide helps people live longer or avoid sudden death. Do not take Flecainide if you are allergic or sensitive to it or if you have heart block (unless you have a cardiac pacemaker).

Flecainide can cause new arrhythmias or worsen already existing ones in 7 percent of people who take it; this risk increases with certain kinds of underlying heart disease and higher doses of the drug. Flecainide may cause or worsen heart failure in about 5 percent of people taking it because it tends to reduce the force and rate of each heartbeat.

Flecainide is extensively broken down in the liver. People with poor liver function should not take Flecainide unless the benefits clearly outweigh the possible risks of drug toxicity.

Possible Side Effects

  • Most common: dizziness, fainting, light-headedness, unsteadiness, visual disturbances (blurred vision, seeing spots before the eyes), difficulty breathing, headache, nausea, fatigue, heart palpitations, chest pain, tremors, weakness, constipation, bloating, and abdominal pain.
  • Less common: new or worsened heart arrhythmias or heart failure, heart block, slowed heart rate, vomiting, diarrhea, upset stomach, loss of appetite, stomach gas, a bad taste in your mouth, dry mouth, tingling in the hands or feet, partial or temporary paralysis, loss of muscle control, flushing, sweating, ringing or buzzing in the ears, anxiety, sleeplessness, depression, feeling sick, twitching, weakness, convulsions, speech disorders, stupor, memory loss, personality loss, nightmares, a feeling of. apathy, eye pain, unusual sensitivity to bright light, sagging eyelids, reduced white-blood-cell or blood-platelet counts, male impotence, reduced sex drive, frequent urination, urinary difficulty, itching, rash, fever, muscle aches, closing of the throat, and swollen lips, tongue, or mouth.

Drug Interactions

  • The combination of Propranolol and Flecainide can cause an exaggerated lowering in heart rate. Other drugs that slow the heart may also interact with Flecainide to produce an excessive slowing of heart rate.
  • The acidity of your urine affects the passing of Flecainide out of your body. Less acidity increases the amount of drug released, and more acidity, such as can occur with megadoses of vitamin C, decreases the amount you release. Extreme changes in urine acid content can expose you to more side effects (more acid) or fewer drug effects (less acid).
  • The amount of Flecainide in your blood and its effect on your heart can be increased if it is taken together with Amiodarone, Cimetidine, Disopyramide, or Verapamil.
  • Cigarette smoking increases the rate at which Flecainide is broken down in the liver. Smokers may need a larger dose than nonsmokers.
  • Flecainide may increase the amount of Digoxin in the bloodstream, increasing the chance of drug side effects.

Food Interactions

Flecainide can be taken without regard to food or meals.

Usual Dose of Flecainide (Tambocor)

The usual starting dose for all age groups is 50 to 100 mg every 12 hours. Your doctor can increase your dose by 50 mg each time every several days, if needed. The maximum dose of Flecainide depends on your response to the drug, your kidney function, and the specific arrhythmia being treated, but can go up to 600 mg per day.


Flecainide overdosage affects heart function, causing slower heart rate, low blood pressure, and possible death from respiratory failure. Victims of Flecainide overdose should be taken to a hospital emergency room for treatment. ALWAYS bring the medicine bottle.

Special Information

Flecainide can make you dizzy, light-headed, or disoriented. Take care while driving or performing any complex tasks.

Call your doctor if you develop chest pains; an abnormal heartbeat, difficulty breathing, bloating in your feet or legs, tremors, fever, chills, sore throat, unusual bleeding or bruising, yellowing of the whites of your eyes, or any other intolerable side effect.

If you forget to take a dose of Flecainide and remember within 6 hours, take it as soon as possible. If you don’t remember until later, skip the forgotten dose and continue with your regular schedule. Do not take a double dose.

Special Populations of Flecainide (Tambocor)

Animal studies have shown that Flecainide at 4 times the normal human dose damages a developing fetus, but it is not known if the drug passes into fetal blood circulation. Pregnant women should discuss with their doctors the potential benefits of taking this drug versus its potential dangers.
Flecainide passes into mother’s milk in concentrations about 2 ½ times that found in blood. Nursing mothers who must take this drug should bottle-feed their infants.

Seniors with reduced kidney or liver function are more likely to develop drug side effects and require a lower dosage.