Consumer medicine information

Xylocard

Lidocaine (lignocaine) hydrochloride

BRAND INFORMATION

Brand name

Xylocard

Active ingredient

Lidocaine (lignocaine) hydrochloride

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using Xylocard.

What is in this leaflet

This leaflet answers some of the common questions people ask about XYLOCARD. It does not contain all the information that is known about XYLOCARD.

It does not take the place of talking to your doctor or pharmacist.

All medicines have risks and benefits. Your doctor will have weighed the risks of you taking XYLOCARD against the benefits they expect it will have for you.

Keep this leaflet with the medicine. You may need to read it again.

What XYLOCARD is for

XYLOCARD is used to change an abnormal beat in the heart back to normal. It works by slowing nerve impulses and reducing the excitability of the heart.

XYLOCARD belongs to a group of medicines known as antiarrhythmics.

Your doctor will have explained why you are being treated with XYLOCARD and told you what dose you will be given.

Follow all directions given to you by your doctor carefully. They may differ from the information contained in this leaflet.

Your doctor may prescribe this medicine for another use. Ask your doctor if you want more information.

XYLOCARD is not addictive.

Before you are given XYLOCARD

When you must not use it

If you are pregnant or breastfeeding do not use XYLOCARD unless your doctor says so. Ask your doctor about the risks and benefits of using this medicine while you are pregnant or breastfeeding. XYLOCARD has been widely used during pregnancy and there have been no reports of any ill effects on the baby.

Your baby can take in very small amounts of XYLOCARD from breast milk if you are breastfeeding, but it is unlikely that the amount available to the baby will do any harm.

XYLOCARD will only be used if the solution is clear, the package is undamaged and the use by (expiry) date marked on the pack has not been passed.

Before you are given it

You must tell your doctor if:

  1. you have any allergies to
  • ingredients listed at the end of this leaflet
  • other antiarrhythmic medicines
  • local anaesthetics eg. bupivacaine
  • other substances

If you have an allergic reaction, you may get a skin rash, hay fever, difficulty breathing or feel faint.

  1. you have any of these medical conditions
  • a pace maker
  • any other heart problems
  • liver problems
  • kidney problems
  • malignant hyperthermia

It may not be safe for you to take XYLOCARD if you have any of these conditions.

Taking other medicines

Tell your doctor if you are taking any other medicines, including

  • ones to control your heart beat
  • ones for blood pressure (anti-hypertensives)
  • ones for epilepsy or fits
  • cimetidine
  • alcohol
  • any medicines that you buy at the chemist, supermarket or health food shop.

These medicines may affect the way XYLOCARD works.

Your doctor or pharmacist can tell you what to do if you are taking any of these medicines.

If you have not told your doctor about any of these things, tell them before you are given any XYLOCARD.

How XYLOCARD is given

XYLOCARD will be injected by your doctor directly into the bloodstream or will be added to fluids given into the vein. This allows XYLOCARD to reach the heart quickly, where it will reduce the excitability of the heart and help return the heart beat to normal.

The dosage you will be given will depend on your body size, age and medical condition. Your doctor will have had a lot of experience injecting XYLOCARD or other antiarrhythmics, and will choose the best dose for you. They will be willing to discuss this decision with you.

Overdose

The doctor giving you XYLOCARD will be experienced in the use of antiarrhythmic drugs, so it is unlikely that you will be given an overdose. However, if you are particularly sensitive to XYLOCARD, you may develop problems such as nervousness, dizziness, blurred vision, tremor or drowsiness.

Whenever you are given XYLOCARD, equipment will be available to care for you if an overdose happens.

While you are being given it

Things to be careful of

Be careful driving or operating machinery after you have been given XYLOCARD. You may be drowsy and your reflexes may be slow.

Do not drink alcohol while you are being given XYLOCARD. If you drink alcohol while you are being given XYLOCARD your blood pressure may drop making you feel dizzy and faint.

Please talk to your doctor or pharmacist about these possibilities if you think they may bother you.

Side effects

Tell your doctor or nurse as soon as possible if you do not feel well while you are being given XYLOCARD. XYLOCARD will return abnormal heart beats back to normal in most people, but it may have unwanted side-effects. All medicines can have side effects. Sometimes they are serious, most of the time they are not. You may need medical treatment if you get some of the side effects.

Ask your doctor, nurse or pharmacist to answer any questions you may have.

Tell your doctor or nurse if you notice any of the following and they worry you:

  • drowsiness
  • lightheadedness
  • nervousness
  • dizziness
  • feeling strange (disoriented)
  • blurred vision
  • ringing in the ears
  • vomiting
  • twitching
  • tremors
  • feeling hot, cold or numb
  • difficulty swallowing
  • slurred speech

These are all mild side effects of XYLOCARD.

If XYLOCARD is given wrongly, or you are very sensitive to it, it sometimes causes:

  • fits
  • unconsciousness
  • breathing problems
  • low blood pressure
  • slow heart beat
  • collapse
  • a problem with your blood called methaemoglobinaemia

These are all serious side effects. You may need urgent medical attention.

Some people may get other side effects while taking XYLOCARD.

Tell your doctor if you notice anything else that is making you feel unwell.

After using it

Storage

XYLOCARD will be stored by your doctor or pharmacist under the recommended conditions.

It should be kept in a cool dry place where the temperature stays below 25 degrees C.

Disposal

Any XYLOCARD from a single dose which is not used , will be disposed of in a safe manner by your doctor or pharmacist.

Product description

All XYLOCARD solutions are clear and colourless.

XYLOCARD 100* solution contains lidocaine (lignocaine) hydrochloride 2% as the active ingredient;
plus,
Sodium chloride
Sodium hydroxide
Water for Injections

XYLOCARD 500 and XYLOCARD 1000* solutions contain lidocaine (lignocaine) hydrochloride 10% as the active ingredient;
plus,
Sodium hydroxide
Water for Injections

Lidocaine is the new name for lignocaine.

Sponsor

Aspen Pharmacare Australia Pty Ltd
34-36 Chandos St
St Leonards NSW 2065
Australia

This leaflet was revised in August 2017

Australian Registration Numbers

Xylocard 100* 12032

Xylocard 500 12036

Xylocard 1000* 12035

* Not currently marketed.

®Trade Marks herein are the property of the AstraZeneca group

Published by MIMS November 2020

BRAND INFORMATION

Brand name

Xylocard

Active ingredient

Lidocaine (lignocaine) hydrochloride

Schedule

S4

 

1 Name of Medicine

Lidocaine (lignocaine) hydrochloride.

2 Qualitative and Quantitative Composition

The active ingredient in Xylocard is lidocaine (lignocaine) hydrochloride.
Plain aqueous solutions are sterile, isotonic and contain lidocaine (lignocaine) hydrochloride, sodium hydroxide for pH adjustment and water for injections.

3 Pharmaceutical Form

All Xylocard solutions are clear and colourless.

4 Clinical Particulars

4.1 Therapeutic Indications

Lidocaine (lignocaine) is classed as a membrane stabilizing agent; local anaesthetic and antiarrhythmic agent. It is extremely stable and plain solutions can be sterilised by autoclaving, repeated if necessary.

Cardiac arrhythmias.

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.

4.2 Dose and Method of Administration

Xylocard solutions contain no antimicrobial agent and should be used in one patient on one occasion only and any residue discarded.

Cardiac arrhythmias.

Dosage is individual. The therapeutic serum concentration range is 5 - 20 micromol/L, 1.5 - 6.0 microgram/mL.
In the treatment of ventricular arrhythmias an intravenous injection should be given first, followed by an intravenous infusion.

Adults.

Preinfusion.

Intravenous.

To obtain therapeutic blood levels rapidly, use lidocaine (lignocaine) 100 mg/5 mL in a dose of lidocaine (lignocaine) 1 mg/kg bodyweight. Inject slowly IV, over a period of 1 to 2 minutes.
The initial effect occurs in 2 to 4 minutes; maximum effect in about 10 minutes; duration 15 to 20 minutes. Infusion should be commenced within 10 minutes.
In the pre-hospital phase 50 - 100 mg doses may be administered at 10 to 20 minute intervals. This dose corresponds to 1 mg/kg body weight per injection. No more than 200 - 300 mg lidocaine (lignocaine) should be administered during a one-hour period. Patients with cardiogenic shock may require smaller bolus doses.

Infusion.

Use Xylocard 500 (100 mg lidocaine (lignocaine)/mL ampoules). A drip rate of 2 to 4 mg/min is recommended. For complicating factors, see Section 4.4 Special Warnings and Precautions for Use.
In order to maintain therapeutic blood levels in the first few hours of infusion therapy, the initial IV injection may be followed by a further two injections of 50 to 100 mg (lidocaine (lignocaine) 100 mg/5 mL) at 15 to 20 minute intervals. This is necessitated by the fairly slow rise to therapeutic concentrations. No more than 200 - 300 mg lidocaine (lignocaine) should be administered in a one-hour period.
In certain cases, doses higher than 4 mg/min may be needed to achieve antiarrhythmic effect. The risk of side effects increases with higher doses, however.
The duration of infusion is normally two or more days. It should normally not be discontinued until 24 hours after the last signs of ventricular tachyarrhythmias or serious ventricular ectopic beats.
The rate of intravenous infusion 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 required to continue intravenous infusions of Xylocard for prolonged periods.

Increase in dosage.

Before increasing the infusion rate, a slow IV injection of 25 to 100 mg should be given to obtain therapeutic blood levels rapidly.

Preparation of infusion solutions.

A concentration of 2 mg lidocaine (lignocaine) per mL is normally used. With higher doses, and in cases in which it is desired to limit the administration of fluid, a higher concentration may be used.
Xylocard may be diluted with 5.5% glucose, invertose, dextran, physiological saline, Ringer's and sodium bicarbonate solutions.
The addition of medicines to infusion solutions always means an added risk with regard to sterility, stability and incompatibility. As a rule, infusion solutions with approved additives should, therefore, be used within 12 hours.

Caution.

During infusion therapy with Xylocard, the rate of administration must be carefully checked, preferably by means of a drop counter or the use of a special infusion pump. The total amount of Xylocard added to the infusion solution may be lethal if infused too rapidly.
The therapeutic dose regimens described are guides only, and because of large intrapatient (with time) and interpatient variability in the response to lidocaine (lignocaine), it is advisable to monitor plasma levels and adjust doses accordingly.
In the case of shock, cardiac or hepatic failure, or the elderly, the dose should be reduced. (See Section 4.4 Special Warnings and Precautions for Use.)

4.3 Contraindications

Stokes-Adams syndrome, or severe degrees of sinoatrial, atrioventricular or intraventricular block. Lidocaine (lignocaine) suppresses ventricular pacemaker activity and the result may be ventricular standstill in such patients.
In the treatment of supraventricular arrhythmias.
Known history of allergy or hypersensitivity to lidocaine (lignocaine) or other amide-type local anaesthetics such as prilocaine, mepivacaine or bupivacaine. See Section 4.5 Interactions with Other Medicines and Other Forms of Interactions.

4.4 Special Warnings and Precautions for Use

1. Resuscitative equipment and medicines, including oxygen, should be immediately available when Xylocard is used, to manage possible lidocaine (lignocaine)-induced reactions involving the cardiovascular, respiratory or central nervous system (see Section 4.8 Adverse Effects (Undesirable Effects)).
2. Constant ECG monitoring is essential for the proper IV administration of lidocaine (lignocaine). Signs of excessive depression of cardiac conductivity, such as prolongation of PR interval and QRS complex, should be followed by prompt cessation of the IV infusion.
3. In emergency situations, when a ventricular rhythm disorder is suspected, and ECG equipment is not available, a single dose may be administered when the physician in attendance has determined that the potential benefits outweigh the possible risks.
4. Mortality. In the Cardiac Arrhythmia Suppression Trial (CAST), a long term, multi-centred, randomised, double-blind study in patients with asymptomatic non-life-threatening ventricular arrhythmia who had myocardial infarction more than 6 days but less than 2 years previously, an excess mortality and non-fatal cardiac arrest rate was seen in patients treated with encainide or flecainide (56/730), compared with that seen in patients assigned to matched placebo-treated groups (22/725). The average duration of treatment with encainide or flecainide in this study was ten months. While there are no comparable mortality trial data for other class I antiarrhythmic agents post myocardial infarction or in other clinical settings, meta-analyses of small scale clinical trials of these agents in similar populations suggests a trend towards increased mortality compared to placebo and no evidence of benefit.
All Class I antiarrhythmic agents share the capacity to produce slowing of conduction velocity which can promote tachycardias via a re-entry mechanism. Indeed, the use of these agents for other than life-threatening arrhythmias or severe symptoms due to arrhythmias is not recommended.
In the light of this information, it is prudent to consider the prophylactic use of Class I antiarrhythmic medicines following myocardial infarction as potentially hazardous.
5. Lidocaine (lignocaine) should be given with caution to patients with severe shock, bradycardia, hypovolaemia, cardiac conduction disturbances (see Section 4.3 Contraindications), severe digitalis intoxication. In the case of bradycardia complicated by ventricular tachyarrhythmia, Xylocard might be combined with atropine or an atropine-like medicine or pacemaker treatment.
6. Since antiarrhythmic medicines may be ineffective in patients with hypokalaemia, serum potassium levels should be normalised prior to Xylocard administration. Hypoxia and acid-base disturbances should also be corrected as these factors may potentiate ventricular arrhythmias.
7. The IV dose of Xylocard should not exceed 100 mg in a single injection, and no more than 200 - 300 mg in a one hour period (see Section 4.2 Dose and Method of Administration) as a hypotensive response is sometimes observed with IV administration of lidocaine (lignocaine).
8. Patients with reduced hepatic blood flow or function, and those on prolonged infusions of lidocaine (lignocaine), have a longer lidocaine (lignocaine) half life and lower clearance resulting in accumulation of lidocaine (lignocaine). Patients with congestive cardiac failure have a reduced clearance. In patients with renal failure, accumulation of lidocaine (lignocaine) and its metabolites may develop during prolonged or repeated administration. These patients may therefore require a reduction in dosage.
9. Patients with a chronic elevation in cardiac output or a drug-induced induction of hepatic microsomal enzymes will have a reduced elimination half-life of lidocaine (lignocaine) and may therefore require a higher dosage.
10. Debilitated, elderly or acutely ill patients should be given reduced doses commensurate with their age and physical status.
11. Dosage reduction may be required during concomitant use with propranolol, metoprolol or cimetidine as there is a possibility of reduced elimination of lidocaine (lignocaine).
12. Lidocaine (lignocaine) should be used with caution in patients with genetic predisposition to malignant hyperthermia as the safety of amide local anaesthetic agents in these patients has not been fully assessed.
13. Blood lidocaine (lignocaine) concentrations should be measured in patients in shock who may have markedly reduced lidocaine (lignocaine) clearance, on prolonged infusions of greater than 24 hours duration especially in patients with cardiac or hepatic failure, those who are refractory to the usual dosage given, and in the presence of ambiguous signs and symptoms of lidocaine (lignocaine) toxicity. Severe reactions are often preceded by somnolence and paraesthesia, therefore these symptoms should not be dismissed.
14. Caution should be observed in patients with cardiac decompensation and hypotension or posterior diaphragmal infarction with a tendency towards development of heart block.
15. When high doses are used and the patient's myocardial function is impaired, combination with other medicines which reduce the excitability of cardiac muscle requires caution.
16. Theoretical evidence suggests that lidocaine (lignocaine) may have porphyrogenic properties. The clinical significance of this is unknown. Caution should be exercised if intravenous Xylocard is administered to patients with acute porphyria.

Use in hepatic impairment.

Patients with reduced hepatic blood flow or function, and those on prolonged infusions of lidocaine (lignocaine), have a longer lidocaine (lignocaine) half-life and lower clearance and may therefore require a reduction in dosage. To lessen the risk of acute toxicity, a regimen with 2 boluses 10 - 30 min apart followed by an infusion is preferable to a single bolus followed by infusion.

Use in renal impairment.

Impairment of renal function is unlikely to affect lidocaine (lignocaine) clearance in the short term (24 hours). However, toxicity due to accumulation of lidocaine (lignocaine) and its metabolites may develop with prolonged or repeated administration.

Use in the elderly.

A reduction in dosage may be necessary for elderly patients with compromised cardiovascular and/or hepatic function and/or on prolonged infusions.

Paediatric use.

The safety of lidocaine (lignocaine) in the treatment of arrhythmias in children has not been established. Through their lower enzyme capacity, neonates are at risk of methaemoglobinaemia which can become clinically overt (cyanosis).

Effects on laboratory tests.

1. Creatinine. Creatinine measurements in patients with therapeutic plasma levels of lidocaine (lignocaine) are about 15 - 35% higher when measured by an enzymatic method versus the Jaffe method. This appears to be due to assay interference from N-ethylglycine, a metabolite of lidocaine (lignocaine).

4.5 Interactions with Other Medicines and Other Forms of Interactions

1. Anti-arrhythmic medicines.

Local anaesthetics of the amide type, such as lidocaine (lignocaine), should be used with caution in patients receiving anti-arrhythmic medicines (e.g. disopyramide, procainamide, mexiletine), since potentiation of cardiac effects may occur.

2. Amiodarone.

Amiodarone has been reported to reduce the clearance of lidocaine (lignocaine) in two case reports, although a small prospective study of combined therapy on lidocaine (lignocaine) pharmacokinetics found no change in clearance or other pharmacokinetic factor. This combination has been reported to precipitate seizures and to lead to severe sinus bradycardia and a long sinoatrial arrest. Until more experience with concurrent use of lidocaine (lignocaine) and amiodarone becomes available, patients receiving the combination should be monitored carefully.

3. Beta-adrenoreceptor antagonists.

Propranolol, nadolol and metoprolol reduce the metabolism of IV administered lidocaine (lignocaine) and the possibility of this effect with other beta-adrenergic blockers should be kept in mind. If these medicines are administered concurrently, the patient should be closely observed for signs of lidocaine (lignocaine) toxicity.

4. Cimetidine.

Cimetidine reduces the clearance of IV administered lidocaine (lignocaine) and toxic effects due to high serum lidocaine (lignocaine) levels have been reported when these two medicines have been administered concurrently.

5. Anticonvulsive agents.

Phenytoin and other antiepileptic medicines such as phenobarbitone, primidone and carbamazepine appear to enhance the metabolism of lidocaine (lignocaine) but the significance of this effect is not known. Phenytoin and lidocaine (lignocaine) have additive cardiac depressant effects.

6. Fluvoxamine.

Coadministration of fluvoxamine drastically reduces the elimination of lidocaine (lignocaine).

7. Inhalational anaesthetics.

Lidocaine (lignocaine) decreases the minimum effective concentration of inhalational anaesthetics, e.g. nitrous oxide.

8. Skeletal muscle relaxants.

Lidocaine (lignocaine) and skeletal muscle relaxants, e.g. suxamethonium, lead to excessive neuromuscular blockade; therefore this combination must be used with caution.

9. Alcohol.

There have been no reports of direct interaction between alcohol and lidocaine (lignocaine). However, acute severe alcohol intoxication can centrally depress the cardiovascular system and may thereby prolong lidocaine (lignocaine) elimination half-life.

10. Potential for influence of lidocaine (lignocaine) on the plasma levels/effect of other medicines.

Lidocaine (lignocaine) is metabolised by CYP1A2 and CYP3A4 and thus has the potential to inhibit the metabolism of medicines metabolised by these isoenzymes, thus increasing their plasma levels, however, this effect has so far not been reported.

11. Potential for influence of other medicines on the plasma levels/effect of lidocaine (lignocaine).

Concomitant treatment with medicines that are substrates, inhibitors or inducers of CYP1A2 or CYP3A4 has the potential to influence the metabolism and hence the plasma levels and effect of lidocaine (lignocaine).

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

See Section 5.3 Preclinical Safety Data.
(Category A)
The safe use of lidocaine (lignocaine) during pregnancy has not been established. Although lidocaine (lignocaine) has been used extensively for surgical procedures during pregnancy with no reports of ill effects to mother or foetus, there are no adequate or well-controlled studies in pregnant women of the effect of lidocaine (lignocaine) on the developing foetus.
Lidocaine (lignocaine) passes into breast milk. The amount of lidocaine (lignocaine) appearing in breast milk from nursing mother receiving parenteral lidocaine (lignocaine) is unlikely to lead a significant accumulation of the parent drug in the breast fed infant. The remote possibility of an idiosyncratic or allergic reaction in the breast fed infant from lidocaine (lignocaine) remained to be determined.

4.7 Effects on Ability to Drive and Use Machines

The effects of this medicine on a person's ability to drive and use machines were not assessed as part of its registration.

4.8 Adverse Effects (Undesirable Effects)

Reactions to lidocaine (lignocaine) hydrochloride are similar in character to those observed with other local anaesthetics.
Adverse experiences are, in general, dose-related and may result from high plasma levels or from a hypersensitivity, idiosyncrasy or diminished tolerance.
Serious adverse events are generally systemic in nature, the following types are those more commonly reported.

Central nervous system.

CNS manifestations are excitatory and/or depressant and may be characterised by lightheadedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, disorientation, tinnitus, double or blurred vision, vomiting, sensations of heat, cold or numbness, paraesthesia, twitching, tremors, convulsions, unconsciousness, psychosis, dyspnoea, respiratory depression and/or arrest, agitation, difficulty swallowing and slurred speech.
The excitatory manifestations 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. Drowsiness following administration of lidocaine (lignocaine) is usually an early sign of a high blood level of the drug and may occur as a result of rapid absorption. In unconscious patients, circulatory collapse should be watched for as CNS effects may not be apparent, as an early manifestation of toxicity may in some cases progress to frank convulsions and ultimately lead to respiratory depression and/or arrest. It is crucial to have resuscitative equipment and anticonvulsant medicines available to manage such patients (see Section 4.9 Overdose, Treatment of overdosage).

Cardiovascular.

Cardiovascular manifestations are usually depressant and are characterised by bradycardia, hypotension, and cardiovascular collapse, which may lead to cardiac arrest. Methaemoglobinaemia can occur following IV administration, particularly in neonates. Arrhythmias including ventricular tachycardia/ ventricular fibrillation.

Allergic.

Allergic reactions are characterised by cutaneous lesions, urticaria, oedema or anaphylactoid reactions. Allergy to amide type local anaesthetics is very rare.

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at www.tga.gov.au/reporting-problems.

4.9 Overdose

Toxicity is initially manifested as CNS excitation and may result in a slow onset of nervousness, dizziness, blurred vision and tremors followed by drowsiness, convulsions, unconsciousness and possibly respiratory arrest.
Cardiovascular toxic effects are generally preceded by signs of toxicity in the central nervous system, unless the patient is receiving a general anaesthetic or is heavily sedated with medicines such as a benzodiazepine or a barbiturate. Toxic cardiovascular reactions are usually depressant in nature, may occur rapidly and with little warning and can lead to peripheral vasodilation, hypotension, myocardial depression and bradycardia. In rare cases, cardiac arrest has occurred without prodromal CNS effects.

Treatment of overdosage.

Discontinue administration of Xylocard. Maintain a patent airway and support ventilation with oxygen and assisted or controlled respiration as required.
Should a convulsion persist despite ventilation therapy, small increments of a benzodiazepine (e.g. diazepam) or an ultra short acting barbiturate (e.g. thiopentone) may be given intravenously.
Cardiovascular depression may require circulatory assistance in the form of elevation of legs, intravenous fluids and/or vasopressor agents, volume expanders and, if necessary, cardiac massage.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Lidocaine (lignocaine) stabilises all potentially excitable membranes including those of nerve, muscle and secretory cells. Its depression of electrical activity in membranes of such cells is reversible.
In cardiac tissue, a therapeutic serum concentration of lidocaine (lignocaine) (5 to 20 micromol/L or 1.5 to 6.0 microgram/mL) has the following effects.
1. Depresses slow spontaneous depolarisation (phase 4), that is, the automaticity of isolated non-depolarized Purkinje fibres, but has little effect on conduction velocity, membrane responsiveness (rate of rise of phase 0) and cardiac output. Automaticity induced by stretch, hypoxia and catecholamines can also be suppressed by lidocaine (lignocaine).
2. Shortens both the action potential period and effective refractory period of Purkinje and ventricular cells. However, the effective refractory period is not reduced to the same extent and the ratio of effective refractory period to action potential duration is increased.
3. In the presence of high extracellular potassium ion concentration, or in myocardial ischaemia where the cells are partially depolarized, depresses the membrane responsiveness (rate of rise of phase 0) and thereby conduction velocity in Purkinje fibres and ventricular myocardium.

Clinical trials.

No data available.

5.2 Pharmacokinetic Properties

Absorption and distribution.

During the first half hour after an intravenous injection, the blood level of lidocaine (lignocaine) declines with a half life of 7 - 10 minutes due to the rapid distribution to various tissues, including the heart. After this initial phase, the half life is 90 - 120 minutes (metabolism and excretion). During continuous infusion, steady-state is reached after 6 - 8 hours.

Metabolism and excretion.

Lidocaine (lignocaine) is metabolised mainly in the liver and excreted via the kidneys. Approximately 90% of administered lidocaine (lignocaine) is excreted in the form of various metabolites while less than 10% is excreted unchanged. The principal metabolites, monoethylglycinexylidide and glycinexylidide, also possess antiarrhythmic action, but to less extent.

5.3 Preclinical Safety Data

Carcinogenicity.

A two-year oral toxicity study of 2,6-xylidine, a metabolite of lidocaine (lignocaine), has shown that in both male and female rats, 2-6-xylidine in daily doses of 900 mg/m2 (150 mg/kg) resulted in carcinomas and adenomas of the nasal cavity. No nasal tumours were observed in the low dose (15 mg/kg or control animals). In addition, the compound also caused subcutaneous fibromas and or fibrosarcomas in male and female rats (significant at 150 mg/kg).

Genotoxicity.

The genotoxic potential of 2,6-xylidine has been studied with mixed results: Positive results were reported in assays for gene mutations (weakly positive in the Ames test with metabolic activation and in the mouse lymphoma assay) and chromosomal damage (chromosomal aberrations in Chinese hamster ovary cells at concentrations at which the drug precipitated from solution). No evidence of genotoxicity was found in in vivo assays for chromosomal damage (micronucleus assay) and DNA damage (unscheduled DNA synthesis). Covalent binding studies of DNA from liver and ethmoid turbinates in rats indicate that 2,6-xylidine may be genotoxic under certain conditions in vivo.

6 Pharmaceutical Particulars

6.1 List of Excipients

See Section 2 Qualitative and Quantitative Composition.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Xylocard should be stored at 25°C or below.

6.5 Nature and Contents of Container

All Xylocard solutions are available as follows:

Bolus IV solutions for injection.

Xylocard 100 2% (100 mg/5 mL): 5 mL ampoule with disposable syringe.*

Infusion solutions.

Xylocard 500 10% (500 mg/5 mL): 10 x 5 mL Polyamp Duofit.
Xylocard 1000 10% (1000 mg/10 mL): 5 x 10 mL ampoules.*
* Not currently marketed.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of in accordance with local requirements.

6.7 Physicochemical Properties

The chemical name for lidocaine (lignocaine) hydrochloride is 2 Diethylaminoaceto 2',6' xylidide hydrochloride.
White crystalline powder which, at 20°C, is soluble in 0.7 parts water; 1.5 parts ethanol (96%); practically insoluble in ether.
Plain aqueous solutions of lidocaine (lignocaine) hydrochloride have a pH of 5.0 - 7.0. Lidocaine (lignocaine) base has a pKa of 7.85 (25°C) and a molecular weight of 234.3.

Chemical structure.

The chemical structure of lidocaine (lignocaine) is:

CAS number.

The CAS number for lidocaine (lignocaine) hydrochloride is 73-78-9.

7 Medicine Schedule (Poisons Standard)

Schedule 4 - Prescription Only Medicine.

Summary Table of Changes