What is this medication?
FLECAINIDE (FLEK a nide) prevents and treats a fast or irregular heartbeat (arrhythmia). It is often used to treat a type of arrhythmia known as AFib (atrial fibrillation). It works by slowing down overactive electric signals in the heart, which stabilizes your heart rhythm. It belongs to a group of medications called antiarrhythmics.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Tambocor
What should I tell my care team before I take this medication?
They need to know if you have any of these conditions:
- Abnormal levels of potassium in the blood
- Heart disease including heart rhythm and heart rate problems
- Kidney or liver disease
- Recent heart attack
- An unusual or allergic reaction to flecainide, local anesthetics, other medications, foods, dyes, or preservatives
- Pregnant or trying to get pregnant
How should I use this medication?
Take this medication by mouth with a glass of water. Follow the directions on the prescription label. You can take this medication with or without food. Take your doses at regular intervals. Do not take your medication more often than directed. Do not stop taking this medication suddenly. This may cause serious, heart-related side effects. If your care team wants you to stop the medication, the dose may be slowly lowered over time to avoid any side effects.
Talk to your care team regarding the use of this medication in children. While this medication may be prescribed for children as young as 1 year of age for selected conditions, precautions do apply.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
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.
What may interact with this medication?
Do not take this medication with any of the following:
- Arsenic trioxide
- Certain antibiotics like clarithromycin, erythromycin, gatifloxacin, gemifloxacin, levofloxacin, moxifloxacin, sparfloxacin, or troleandomycin
- Certain antidepressants called tricyclic antidepressants like amitriptyline, imipramine, or nortriptyline
- Certain medications to control heart rhythm like disopyramide, encainide, moricizine, procainamide, propafenone, and quinidine
- Medications for malaria like chloroquine and halofantrine
- Phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine
This medication may also interact with the following:
- Medications for angina or high blood pressure
- Medications to control heart rhythm like amiodarone and digoxin
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medication?
Visit your care team for regular checks on your progress. Because your condition and the use of this medication carries some risk, it is a good idea to carry an identification card, necklace or bracelet with details of your condition, medications, and care team.
Check your blood pressure and pulse rate regularly. Ask your care team what your blood pressure and pulse rate should be, and when you should contact them. Your care team also may schedule regular blood tests and electrocardiograms to check your progress.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medication affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol can make you more dizzy, increase flushing and rapid heartbeats. Avoid alcoholic drinks.
What side effects may I notice from receiving this medication?
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Heart failure—shortness of breath, swelling of the ankles, feet, or hands, sudden weight gain, unusual weakness or fatigue
- Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
- Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Blurry vision
- Tremors or shaking
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medication?
Keep out of the reach of children and pets.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light. Keep container tightly closed. Throw away any unused medication after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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