INDICATIONS AND USAGE Lidocaine hydrochloride injection administered intravenously or intramuscularly, is specifically indicated in the acute management of ventricular arrhythmias such as those occurring in relation to acute myocardial infarction, or during cardiac manipulation, such as cardiac surgery.

WARNINGS IN ORDER TO MANAGE POSSIBLE ADVERSE REACTIONS, RESUSCITATIVE EQUIPMENT, OXYGEN AND OTHER RESUSCITATIVE DRUGS SHOULD BE IMMEDIATELY AVAILABLE WHEN LIDOCAINE HYDROCHLORIDE INJECTION IS USED.

Systemic toxicity may result in manifestations of central nervous system depression (sedation) or irritability (twitching), which may progress to frank convulsions accompanied by respiratory depression and/or arrest.

Early recognition of premonitory signs, assurance of adequate oxygenation and, where necessary, establishment of artificial airway with ventilatory support are essential to management of this problem.

Should convulsions persist despite ventilatory therapy with oxygen, small increments of anticonvulsant drugs may be used intravenously.

Examples of such agents include benzodiazepines (e.g., diazepam), ultrashort-acting barbiturates (e.g., thiopental or thiamylal) or a short-acting barbiturate (e.g., pentobarbital or secobarbital).

If the patient is under anesthesia, a short-acting muscle relaxant (e.g., succinylcholine) may be used.

Longer acting drugs should be used only when recurrent convulsions are evidenced.

Should circulatory depression occur, vasopressors may be used.

Constant electrocardiographic monitoring is essential to the proper administration of lidocaine hydrochloride.

Signs of excessive depression of cardiac electrical activity such as sinus node dysfunction, prolongation of the P-R interval and QRS complex or the appearance or aggravation of arrhythmias, should be followed by flow adjustment and, if necessary, prompt cessation of the intravenous infusion of this agent.

Occasionally, acceleration of ventricular rate may occur when lidocaine hydrochloride is administered to patients with atrial flutter or fibrillation.

ADVERSE REACTIONS Adverse experiences following the administration of lidocaine are similar in nature to those observed with other amide local anesthetic agents.

Adverse experiences may result from high plasma levels caused by excessive dosage or may result from a hypersensitivity, idiosyncrasy or diminished tolerance on the part of the patient.

Serious adverse experiences are generally systemic in nature.

The following types are those most commonly reported.

The adverse experiences under Central Nervous System and Cardiovascular System are listed, in general, in a progression from mild to severe.

Central Nervous System: CNS reactions are excitatory and/or depressant and may be characterized by light-headedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, tinnitus, blurred or double vision, vomiting, sensations of heat, cold or numbness, twitching, tremors, convulsions, unconsciousness, respiratory depression and arrest.

The excitatory reactions may be very brief or may not occur at all, in which case, the first manifestation of toxicity may be drowsiness, merging into unconsciousness and respiratory arrest.

Cardiovascular System: Cardiovascular reactions are usually depressant in nature and are characterized by bradycardia, hypotension and cardiovascular collapse, which may lead to cardiac arrest.

Allergic reactions as a result of sensitivity to lidocaine are extremely rare and, if they occur, should be managed by conventional means.

Neurologic: There have been reported cases of permanent injury to extraocular muscles requiring surgical repair following retrobulbar administration.