LIDOCAINE HYDROCHLORIDE

Lidocaine Hydrochloride Injection USP, is a sterile, aqueous solution of lidocaine, an antiarrhythmic agent, prepared with the aid of hydrochloric acid. It is intended for intravenous administration by either direct injection or continuous infusion. Lidocaine hydrochloride is designated 2-(Diethylamino)-2’, 6’-acetoxylidide monohydrochloride and isrepresented by the following structural formula: *pH of the above solution adjusted with sodium hydroxide and/or hydrochloric acid to finished product pH limits between 5 and 7. The medication and fluid pathway of these disposable syringes are sterile and nonpyrogenic in the original, unopened package with component caps in place. These dosage forms do not contain preservatives; once the unit is assembled and used, any remaining portion of the solution must be discarded with the entire unit. Molecular Structure

Lidocaine hydrochloride administered intravenously, 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.

Adults: Single Direct Intravenous Injection (bolus): ONLY THE 50 AND 100 MG DOSAGE SIZES should be used for direct intravenous injection. The usual dose is 50 to 100 mg of lidocaine hydrochloride (0.70 to 1.4 mg/kg; 0.32 to 0.63 mg/lb) administered intravenously under ECG monitoring. This dose may be administered at the rate of approximately 25 to 50 mg/min (0.35 to 0.70 mg/kg/min; 0.16 to 0.32 mg/lb/min). Sufficient time should be allowed to enable a slow circulation to carry the drug to the site of action. If the initial injection of 50 to 100 mg does not produce a desired response, a second dose may be injected after 5 minutes. (See illustrated instructions for use.) NO MORE THAN 200 TO 300 MG OF LIDOCAINE HYDROCHLORIDE SHOULD BE ADMINISTERED DURING A ONE HOUR PERIOD. Continuous Intravenous Infusion: Following bolus administration, intravenous infusions of lidocaine hydrochloride may be initiated at the rate of 1 to 4 mg/min of lidocaine hydrochloride (0.014 to 0.057 mg/kg/min; 0.006 to 0.026 mg/lb/min). The rate of intravenous infusions should be reassessed as soon as the patient’s basic cardiac rhythm appears to be stable or at the earliest signs of toxicity. It should rarely be necessary to continue intravenous infusions of lidocaine for prolonged periods. Solutions for intravenous infusion may be prepared by the addition of one gram (or two grams) of lidocaine hydrochloride to one liter of 5% dextrose in water using aseptic technique. Approximately a 0.1% (or 0.2%) solution will result from this procedure; that is, each milliliter will contain approximately 1 (or 2) mg of lidocaine hydrochloride. In those cases in which fluid restriction is medically appropriate, a more concentrated solution may be prepared. Lidocaine hydrochloride injection has been found to be chemically stable for 24 hours after dilution in 5% dextrose in water. However, as with all intravenous admixtures, dilution of the solution should be made just prior to its administration. It is very important that after adding lidocaine hydrochloride, or any other medication, to an I.V. container, the contents be thoroughly mixed before beginning the infusion. When administering by continuous I.V. infusion, it is advisable to use a precision volume control I.V. set. Pediatric Controlled clinical studies in the pediatric population to establish dosing schedules have not been conducted. The American Heart Association’s Standards and Guidelines recommends a bolus dose of 1 mg/kg, and an infusion rate of between 20 to 50 mcg/kg/min for prolonged therapy. When drug clearance is reduced, as in patients with shock, congestive heart failure or cardiac arrest, the infusion rate should not exceed 20 mcg/kg/min. Note Regarding Prolonged Infusion: There are data that indicate the half-life may be 3 hours or longer following infusions of greater than 24 hours in duration. Note: Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever the solution and container permit.

Lidocaine hydrochloride is contraindicated in patients with a known history of hypersensitivity to local anesthetics of the amide type. Lidocaine hydrochloride should not be used in patients with Stokes-Adams syndrome. Wolff-Parkinson-White syndrome, or with severe degrees of sinoatrial, atrioventricular, or intraventricular block in the absence of an artificial pacemaker.

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. 1. Central Nervous System: CNS reactions are excitatory and/or depressant, and may be characterized by lightheadedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, tinnitus, blurred or dou- ble 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. 2. Cardiovascular System: Cardiovascular reactions are usually depressant in nature and are characterized by bradycardia, hypotension, and cardiovascular collapse, which may lead to cardiac arrest. 3. Allergic reactions as a result of sensitivity to lidocaine are extremely rare and, if they occur, should be managed by conventional means.

Lidocaine hydrochloride should be used with caution in patients with digitalis toxicity accompanied by atrioventricular block. Concomitant use of beta-blocking agents may reduce hepatic blood flow and thereby reduce lidocaine clearance. Lidocaine and tocainide are pharmacologically similar. The concomitant use of these two agents may cause an increased incidence of adverse reactions, including central nervous system adverse reactions such as seizure.