XYLOCARD

What it is

XYLOCARD is lidocaine hydrochloride supplied as solutions for injection and infusion. Plain aqueous solutions are sterile and isotonic, containing lidocaine hydrochloride, sodium hydroxide for pH adjustment and Water for Injections. All XYLOCARD solutions are clear and colourless. Lidocaine is classed as a membrane stabilising agent, local anaesthetic and antiarrhythmic agent.

Approved indications —

Treatment or prophylaxis of life-threatening ventricular arrhythmias, including those associated with myocardial infarction, general anaesthesia in patients predisposed to ventricular arrhythmias, digitalis intoxication, or following resuscitation from cardiac arrest.

Dosing overview

Dosage is individual, with a therapeutic serum concentration range of 5 to 20 micromol/L (1.5 to 6.0 microgram/mL). In the treatment of ventricular arrhythmias an intravenous injection should be given first followed by intravenous infusion. To obtain therapeutic blood levels rapidly, use lidocaine 100 mg/5 mL in a dose of 1 mg/kg bodyweight injected slowly intravenously over 1 to 2 minutes. The initial effect occurs in 2 to 4 minutes, maximum effect in about 10 minutes, and duration is 15 to 20 minutes. For infusion, a drip rate of 2 to 4 mg/min is recommended. The duration of infusion is normally two or more days and should not normally be discontinued until 24 hours after the last signs of ventricular tachyarrhythmias or serious ventricular ectopic beats.

Key safety warnings

Resuscitative equipment and medicines, including oxygen, should be immediately available when XYLOCARD is used to manage possible lidocaine-induced reactions involving the cardiovascular, respiratory or central nervous system. Constant ECG monitoring is essential for proper intravenous administration, and signs of excessive depression of cardiac conductivity such as prolongation of PR interval and QRS complex should be followed by prompt cessation of infusion. Meta-analyses of clinical trials of Class I antiarrhythmic agents suggest a trend towards increased mortality compared to placebo. The use of these agents for other than life-threatening arrhythmias or severe symptoms due to arrhythmias is not recommended, and it is prudent to consider the prophylactic use of Class I antiarrhythmic medicines following myocardial infarction as potentially hazardous. Lidocaine should be given with caution to patients with severe shock, bradycardia, hypovolaemia, cardiac conduction disturbances and severe digitalis intoxication. Serum potassium levels should be normalised prior to XYLOCARD administration as antiarrhythmic medicines may be ineffective in patients with hypokalaemia. Hypoxia and acid-base disturbances should also be corrected as these factors may potentiate ventricular arrhythmias.

Contraindications

XYLOCARD is contraindicated in Stokes-Adams syndrome or severe degrees of sinoatrial, atrioventricular or intraventricular block, as lidocaine suppresses ventricular pacemaker activity and may result in ventricular standstill in such patients. It is contraindicated in the treatment of supraventricular arrhythmias. XYLOCARD is contraindicated in patients with a known history of allergy or hypersensitivity to lidocaine or other amide-type local anaesthetics such as prilocaine, mepivacaine or bupivacaine.

PBS listing

XYLOCARD infusion containing lidocaine hydrochloride 500 mg in 5 mL is listed on the PBS with one item restricted item, at an ex-manufacturer price of A$20.55.

Regulatory history

XYLOCARD was first listed on the Australian Register of Therapeutic Goods on 13 August 1991, with three registered variants: XYLOCARD 100 (100 mg/5 mL injection ampoule kit), XYLOCARD 500 (500 mg/5 mL injection ampoule) and XYLOCARD 1000 (1000 mg/10 mL injection ampoule). The product information was most recently revised on 26 August 2024, with a warning added regarding lidocaine-induced hypersensitivity reactions leading to Kounis syndrome.