Flecainide

Medication Overview

Flecainide is an antiarrhythmic medication used to treat cardiac arrhythmias. It primarily helps control abnormal heart rhythms such as atrial fibrillation, atrial flutter, or supraventricular tachycardia.

This drug works by blocking sodium channels in cardiac cells, slowing electrical impulse conduction, thereby restoring normal heart rhythm. It is typically used for patients who do not respond well to other treatments or cannot tolerate them.

Brand Names and Generic Name

The generic name is Flecainide. Common brand names include "Flecanide®" among others. Different countries may have different brand names, but in Taiwan and Hong Kong, the generic name "Flecainide" is often used directly.

Drug Classification

It belongs to the class of "Sodium Channel Blockers" and is categorized as a Class III antiarrhythmic drug. This classification mainly targets the electrophysiological properties of the heart.

Indications

Primarily used to treat the following conditions:

• Conversion of persistent atrial fibrillation to normal sinus rhythm
• Frequent supraventricular tachycardia
• Prevention of chest pain or dizziness caused by arrhythmias

Note that this medication is only for severe symptoms and when other treatments have failed. It must be prescribed and closely evaluated by a cardiologist.

Common Side Effects

Mild side effects include:

• Dizziness or headache
• Nausea or diarrhea
• Numbness in limbs

Serious side effects require immediate medical attention:

• Bradycardia or cardiac arrest
• Difficulty breathing or chest pain
• Mental confusion or syncope

Warnings and Precautions

Contraindications: Patients with heart failure, severe conduction block, or sick sinus syndrome should not use this medication. Pregnant or breastfeeding women must consult a physician before use.

This drug carries a black box warning for the potential to induce fatal arrhythmias. Regular ECG monitoring is required during treatment, and strict adherence to medical instructions is essential.

Drug Interactions

Concurrent use with the following medications may increase risks:

• Other antiarrhythmic drugs (e.g., Amiodarone)
• Certain antibiotics (e.g., Macrolides)
• Antifungal agents (e.g., Ketoconazole)

When combined with β-blockers or calcium channel blockers, dose adjustments are necessary to prevent electrophysiological abnormalities.

Dosage and Administration

The initial dose is usually 50-100 mg daily, taken once or twice daily. The specific dose should be adjusted based on age, liver and kidney function, and symptom severity.

Tablets should be swallowed whole without chewing, and taken at the same time each day to maintain blood drug levels. Alcohol consumption should be avoided during treatment to prevent exacerbating side effects.

Missed Dose Management

If a dose is missed and more than 4 hours have passed since the scheduled time, take it as soon as possible. If it is close to the next dose, skip the missed dose and resume the regular schedule. Do not double the dose to make up for a missed one.

Do not increase the dose on your own due to missed doses; contact your physician for dose adjustment.

Overdose Management

Overdose can lead to severe arrhythmias or shock. Seek immediate medical attention. Symptoms may include extremely slow pulse, difficulty breathing, or loss of consciousness.

Emergency treatment involves ECG monitoring and intravenous administration of antiarrhythmic agents. Do not attempt self-treatment.

 

Frequently Asked Questions

Are there any special considerations regarding the timing and method of taking Flecainide?

Flecainide should be taken as prescribed, usually on an empty stomach to ensure stable absorption. Swallow the tablet whole with a glass of water, avoiding chewing or breaking it. If a dose is missed, take it immediately; if it is close to the next dose, skip the missed dose. Resume normal dosing the next day and avoid doubling doses.

What should I do if I experience irregular heartbeat or dizziness while taking Flecainide?

If you experience irregular heartbeat, dizziness, or fainting, stop taking the medication immediately and contact your doctor. These may be signs of electrolyte imbalance or arrhythmia caused by the drug. Your doctor may adjust the dose or perform ECG monitoring. Severe arrhythmias require emergency medical attention.

Are there any potential drug interactions I should be aware of when taking Flecainide with other medications?

Flecainide may interact with other antiarrhythmic drugs, antibiotics (e.g., macrolides), antifungal agents, or β-blockers, increasing the risk of arrhythmias. Inform your healthcare provider of all medications you are taking, including prescription and over-the-counter drugs, to avoid adverse effects.

What monitoring tests are recommended for patients on long-term Flecainide therapy?

Patients on long-term Flecainide should undergo regular ECG and blood drug level monitoring to assess heart rhythm and ensure drug levels are within a safe range. Your doctor may also order blood tests to monitor liver and kidney function and electrolyte balance to ensure safe treatment.

Are there any dietary or exercise restrictions while taking Flecainide?

Avoid high-calcium or calcium-antagonist-rich foods to prevent electrolyte imbalance. During exercise, opt for moderate to low-intensity activities. Stop exercising and seek medical attention if chest pain or palpitations occur. Avoid alcohol and spicy foods to reduce the risk of side effects.