International Medication Systems (UK) Ltd

Lidocaine Hydrochloride Injection BP Minijet 2% w/v.

Lidocaine Hydrochloride 20mg/ml; 100mg/5ml.

For excipients see 6.1.

Solution for injection. The clear, colourless, solution is contained in a USP Type I glass vial with an elastomeric closure. The container is specially designed for use with the IMS Minijet injector supplied.

For local anaesthesia by infiltration, intravenous regional anaesthesia and nerve blocks.

By intravenous injection for the emergency management of ventricular arrhythmias, particularly after myocardial infarction and cardiac surgery.

For local anaesthesia:

The dosage varies depending upon the area to be anaesthetised, vascularity of the tissues, number of neuronal segments to be blocked, individual tolerance and the anaesthetic technique. The lowest dosage needed to provide anaesthesia should be administered.

Adults: a maximum dose of 3 mg/kg or 200 mg, whichever is lower, should not be exceeded.

Children: the usual dose should not exceed 3 mg/kg.

Elderly or debilitated patients require smaller doses, commensurate with age and physical status.

For epidurals, a test dose should be administered at least 5 minutes before total dose to prevent inadvertent intravascular or subarachnoid injection.

For continuous epidural, caudal or paracervical anaesthesia, the maximal dose should not be repeated at intervals under 90 minutes.

For i.v. regional anaesthesia (Bier's block), the tourniquet should not be released until at least 20 minutes after administration.

For intravenous use in cardiac arrhythmias:

Adults: the usual dose is 50 to 100 mg administered intravenously under ECG monitoring. This dose may be injected at a rate of approximately 25 to 50 mg (2.5 to 5.0 ml 1% solution or 1.25 to 2.5 ml 2% solution) per minute. A sufficient period of time should be allowed to enable a slow circulation to carry the drug to the site of action. If the initial dose of 50 to 100 mg does not produce the desired response, a second dose may be given after 5 minutes. No more than 200 to 300 mg of lidocaine should be administered during a one hour period.

Following a single injection in those patients in whom arrhythmia tends to recur and who are incapable of receiving oral antiarrhythmic therapy, intravenous infusions of lidocaine may be administered at the rate of 1 to 4 mg/minute (20 to 50 mcg/kg/minute). IV infusions must be given under ECG monitoring to avoid potential overdosage and toxicity. The infusion should be terminated 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 the infusion beyond 24 hours. As soon as possible, patients should be changed to an oral antiarrhythmic agent for maintenance therapy.

Children: experience with lidocaine is limited. A suggested paediatric dose is a loading dose of 0.8 to 1 mg/kg repeated if necessary up to 3-5 mg/kg, followed by continuous infusion of 10 to 50 mcg/kg/minute.

Elderly: doses may need to be reduced depending on age and physical state.

Lidocaine is contraindicated in patients with known hypersensitivity to local anaesthetics of the amide type and in patients with porphyria.

Use in patients with bradycardia, Stokes-Adams syndrome or severe degrees of sinoatrial, atrioventricular or intraventricular block or cardiac decompensation not dependent on tachyarrhythmias.

When used for local anaesthesia, it is important to protect against accidental intravascular injection and to bear in mind that absorption may be rapid from highly vascular areas especially if these are inflamed or traumatized.

Foetal bradycardia frequently follows paracervical block and may be associated with foetal acidosis. Foetal heart rate should always be monitored during paracervical anaesthesia.

Constant ECG monitoring is necessary during IV administration. Resuscitative equipment and drugs should be immediately available for the management of severe adverse cardiovascular, respiratory or central nervous system effects. If severe reactions occur, lidocaine should be discontinued.

Blood pressure should be monitored during epidural, caudal or paracervical anaesthesia.

Use with caution in patients with epilepsy, liver disease, congestive heart failure, severe renal disease, marked hypoxia, severe respiratory depression, hypovolaemia or shock and in patients with any form of heart block or sinus bradycardia. Hypokalaemia, hyperkalaemia, hypoxia and disorders of acid-base balance should be corrected before treatment with lidocaine begins.

Administration of lidocaine to eliminate ventricular ectopic beats without prior acceleration in heart rate may provoke more frequent and serious ventricular arrhythmias.

Continuous or repeated administration may give rise to cumulative toxicity and tachyphylaxis.

Propranolol and cimetidine may reduce the renal and hepatic clearance of lidocaine, thus increasing toxicity. The cardiac depressant effects of lidocaine are additive to those of other antiarrhythmic agents. Lidocaine prolongs the action of suxamethonium.

Epidural administration of lidocaine in combination with clonidine, adrenaline or clonidine plus adrenaline significantly reduces the C_max of lidocaine.

The safe use of lidocaine has not been established with respect to possible adverse effects upon foetal development. Lidocaine is excreted in breast milk and so should be used with caution in nursing women.

Not applicable; this preparation is intended for use only in emergencies.

Adverse effects are usually due to inadvertent intravenous administration or overdosage. Allergic reactions (including anaphylaxis) have been reported rarely.

The following systemic reactions have been reported in association with lidocaine:

Nervous system disorders: light-headedness, drowsiness, dizziness, apprehension, nervousness, euphoria, tinnitus, blurred or double vision, nystagmus, vomiting, sensations of heat, cold or numbness, twitching, tremors, paraesthesia, convulsions, unconsciousness, respiratory depression and arrest, nausea, headache, transient neurological symptoms i.e. pain and/or dysaesthesia in the buttocks or legs.

Cardiac disorders: arrhythmia, hypotension, cardiovascular collapse and bradycardia which may lead to cardiac arrest.

Blood and the lymphatic system disorders: methaemoglobinaemia.

Symptoms: reactions due to overdose with lidocaine (high plasma levels) are systemic and involve the central nervous and cardiovascular systems. Effects include medullary depression, tonic and clonic convulsions and cardiovascular collapse.

Treatment: institute emergency resuscitative procedures and administer the drugs necessary to manage the severe reaction. For severe convulsions, small increments of diazepam or an ultra-short acting barbiturate (thiopentone), or if not available, a short-acting barbiturate (pentobarbitone or quinalbarbitone), or if the patient is under anaesthesia, a short-acting muscle relaxant (suxamethonium) may be given intravenously. Patency of the airway and adequacy of ventilation must be assured.

Should circulatory depression occur vasopressors such as metaraminol may be used.

Lidocaine stabilises the neuronal membrane and prevents the initiation and transmission of nerve impulses, thereby effecting local anaesthetic action. The onset of action is rapid and the blockade may last up to 2 hours.

In the heart, lidocaine reduces automaticity by decreasing the rate of diastolic (phase 4) depolarisation. Lidocaine is considered as a class 1b (membrane stabilising) antiarrhythmic agent. The duration of the action potential is decreased due to blockade of the sodium channel and the refractory period is shortened.

Lidocaine is rapidly distributed to all body tissues. About 65% is plasma bound. Lidocaine crosses the placenta and the blood brain barrier. The plasma half life is 1.6 hours. About 80% of the dose is metabolised in the liver; less than 10% is found unchanged in the urine.

Not applicable since lidocaine has been used in clinical practice for many years and its

effects in man are well known.

Hydrochloric Acid

Sodium Chloride

Sodium Hydroxide

Water for Injection

None known.

3 years.

The product should be used immediately after opening. Discard any unused protion.

Do not store above 25°C.

The solution is contained in a USP type I glass vial with an elastomeric closure which meets all the relevant USP specifications. The product is available as a 2% solution in a 5 ml vial.

The container is specially designed for use with the IMS Minijet injector.

International Medication Systems (UK) Ltd

208 Bath Road

Slough

Berkshire

SL1 3WE

UK

PA 255/4/5

Date of first authorization: 8^th September 1977

Date of last renewal: 8^th September 2002

October 2004

POM