flekainidi

Flekainidi, commonly known as flecainide, is a prescription antiarrhythmic medication used to treat specific types of irregular heartbeats. It is classified as a class Ic antiarrhythmic drug, which blocks fast sodium channels in cardiac tissue, slowing conduction and altering the heart's electrical properties.

Medical uses: It is used to terminate and prevent paroxysmal atrial fibrillation or flutter and other supraventricular tachyarrhythmias in patients without structural heart disease. It may be considered for certain ventricular arrhythmias in carefully selected patients who do not have significant heart disease. It is not recommended for patients with structural heart disease or recent myocardial infarction due to proarrhythmia risk.

Mechanism: It blocks voltage-gated sodium channels during phase 0 of the action potential, reducing depolarization and slowing conduction, especially in atrial tissue. The effect is often reflected on the electrocardiogram as QRS complex widening.

Administration and monitoring: Flekainidi is taken orally in divided doses as prescribed. Dosing is individualized and adjusted based on response and tolerability. ECG monitoring is typically required after initiation or dose changes, along with assessment of renal and hepatic function and other medications. Use requires caution in patients with reduced left ventricular function or ischemic heart disease.

Safety: Common side effects include dizziness, headaches, blurred vision, nausea, and palpitations. More serious risks include bradycardia, AV block, or proarrhythmic events, particularly in those with structural heart disease or electrolyte disturbances.

Contraindications and interactions: It is contraindicated in individuals with significant structural heart disease or heart failure with reduced ejection fraction, and in those with known conduction abnormalities without a functioning escape mechanism. It can interact with other sodium channel blockers and drugs that affect heart rate or conduction, such as beta-blockers and certain antiarrhythmics.