LIDOCAINE

Lidocaine Injection is used as a local anaesthetic when injected subcutaneously. This solution is not intended for use intravenously. Solutions of lidocaine, which contain preservatives, should not be used for spinal, epidural, caudal or intravenous regional anaesthesia.

The dosage should be adjusted according to the response of the patient and the site of administration. The lowest concentration and the smallest dose producing the required effect should be given. The maximum single dose for healthy adults should not exceed 200mg corresponding to 10mls.

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

In common with other local anaesthetics, adverse reactions to lidocaine are rare and are usually the result of raised plasma concentrations due to accidental intravascular injection, excessive dosage or rapid absorption from highly vascular areas, or may result from a hypersensitivity, idiosyncrasy or diminished tolerance on the part of the patient.

Systemic toxicity mainly involves the central nervous system and/or the cardiovascular system (see also

3 Contraindications) congestive cardiac failure, bradycardia, severe shock, impaired respiratory function or impaired renal function with a creatinine clearance of less than 10mL/minute. Lidocaine is metabolised in the liver and it should be used with caution in patients with impaired hepatic function.

Lidocaine should not be used in cases of acute porphyrias. Patients with myasthenia gravis are particularly susceptible to the effects of local anaesthetics. Facilities for resuscitation should be available when administering local anaesthetics.

The effect of local anaesthetics may be reduced if the injection is made into an inflamed or infected area. Certain local anaesthetic procedures may be associated with serious adverse reactions, regardless of the local anaesthetic drug used.

• Retrobulbar injections may rarely reach the cranial subarachnoid space, causing serious/severe reactions, including cardiovascular collapse, apnoea, convulsions and temporary blindness • Retro- and peribulbar injections of local anaesthetics carry a low risk of persistent ocular motor dysfunction.

The primary causes include trauma and/or local toxic effects on muscles and/or nerves. The severity of such tissue reactions is related to the degree of trauma, the concentration of the local anaesthetic and the duration of exposure of the tissue to the local anaesthetic.

For this reason, as with all local anaesthetics, the lowest effective concentration and dose of local anaesthetic should be used. Lidocaine injection in conjunction with solutions containing adrenaline (epinephrine) should be used with caution in patients with hypertension, cardiac disease, cerebrovascular insufficiency, thyrotoxicosis, in patients taking tricyclic antidepressants, MAOI's or receiving potent anaesthetic agents.

Hameln Lidocaine Injection is not recommended for use in neonates. The optimum serum concentration of lidocaine required to avoid toxicity, such as convulsions and cardiac arrhythmias, in this age group is not known.

• Known hypersensitivity to lidocaine or other anaesthetics of the amide type • Known hypersensitivity to hydroxybenzoates • Complete heart block • Hypovolaemia