FDA approved Lidocaine Hydrochloride Injection for Ventricular ArrhythmiasFDA approved lidocaine injection for emergency heart rhythm problems.

Lidocaine is a local anesthetic of the amide type that exerts its antiarrhythmic effect by blocking sodium channels, thereby decreasing automaticity and suppressing reentrant arrhythmias in ventricular tissue. It primarily affects fast-response cardiac tissues, shortening the action potential duration and effective refractory period.

Lidocaine Hydrochloride Injection, USP is indicated for the acute management of: 1) ventricular arrhythmias occurring during cardiac manipulation such as cardiac surgery, and 2) life-threatening arrhythmias, particularly those which are ventricular in origin, such as those occurring during acute myocardial infarction. It is intended for use in adult and pediatric patients, though pediatric dosing is based on American Heart Association guidelines rather than controlled clinical studies.

For adults, the usual dose for direct injection is 50 to 100 mg administered intravenously under ECG monitoring, at a rate of approximately 25 to 50 mg/min. A second dose may be repeated after 5 minutes if the initial response is inadequate. No more than 200 to 300 mg should be administered during a one-hour period. This product is for direct injection only; for continuous infusion, refer to the prescribing information for lidocaine hydrochloride infusion solution. For pediatric patients, the American Heart Association recommends a bolus dose of 1 mg/kg followed by an infusion rate of 30 mcg/kg/min. The vial should be wiped with alcohol prior to use and stored at controlled room temperature (20° to 25°C).

Trial data not available in label.

Warnings: Constant monitoring of the electrocardiogram and blood pressure is essential. If hypotension or excessive depression of cardiac conductivity (e.g., prolongation of PR interval and QRS complex, aggravation of arrhythmias) occurs, discontinue administration. Emergency resuscitative equipment and drugs must be immediately available. Occasional acceleration of ventricular rate may occur in patients with atrial fibrillation. Toxicity may manifest as CNS depression or irritability, progressing to convulsions with respiratory depression; manage with adequate oxygenation, ventilatory support, and anticonvulsants if needed. Contraindications: Known hypersensitivity to amide-type local anesthetics; Stokes-Adams syndrome; Wolff-Parkinson-White syndrome; severe degrees of sinoatrial, atrioventricular, or intraventricular block.

Lidocaine remains a first-line agent for the acute management of ventricular arrhythmias, particularly in the setting of acute myocardial infarction or cardiac surgery. It is a mainstay in emergency and perioperative settings, though its use has declined with the advent of amiodarone and other agents. It is particularly useful when rapid intravenous administration is needed, and it is often included in advanced cardiac life support protocols. Clinicians should be aware of its narrow therapeutic window and the need for continuous monitoring.