Lidocaine

As with any local anaesthetic, reactions and complications are best averted by employing the minimal effective dosage. Debilitated or elderly patients and children should be given doses commensurate with their age and physical condition. The dose of topical lidocaine should be taken into consideration in estimating the total dose of lidocaine if parenteral lidocaine is to be administered concomitantly. The following dosage recommendations should be regarded as a guide. The clinician’s experience and knowledge of the patient’s physical status are of importance in calculating the required dose. One mL of Xylocaine 2% Jelly is approximately equal to one gram of Xylocaine 2% Jelly. Urethral anaesthesia Surface anaesthesia of the male adult urethra: the usual dose required for adequate analgesia in males is 20 mL jelly (= 400 mg lidocaine hydrochloride). The jelly is instilled slowly into the urethra until it reaches the external sphincter, proximal to the prostate, where a certain …

Known history of hypersensitivity to local anaesthetics of the amide type or other components of the jelly. Hypersensitivity to methyl and/or propyl hydroxybenzoate or to their metabolite para aminobenzoic

Warning Excessive dosage, or short intervals between doses, can result in high levels of lidocaine or its metabolites and serious adverse effects. Patients should be instructed to strictly adhere to the recommended dosage and administration guidelines (the management of serious adverse reactions may require the use of resuscitative equipment, oxygen and other resuscitative drugs). The lowest dose that results in effective anaesthesia should be used to avoid high plasma levels and serious adverse effects. Tolerance to elevated blood levels varies with the status of the patient. Dose reduction Debilitated, elderly and/or acutely ill patients and children should be given reduced doses commensurate with their age and physical status. Excessive absorption Absorption from wound surfaces and mucous membranes is relatively high, especially in the bronchial tree. Because of the possibility of significant systemic absorption, Xylocaine 2% Jelly should be used with caution in patients with …

Antiarrhythmic drugs Lidocaine should be used with caution in patients receiving antiarrhythmic drugs, such as mexiletine, since the toxic effects are additive. Specific interaction studies with lidocaine (lidocaine) and anti-arrhythmic drugs class III (e.g. amiodarone) have not been performed, but caution is advised. Enzyme inducing drugs Drugs that reduce the clearance of lidocaine (e.g. cimetidine or betablockers) may cause potentially toxic plasma concentrations when lidocaine is given in repeated high doses over a long time period. Caution should be taken if administered concurrently with lidocaine. However, such interactions should be of no clinical importance following short term treatment with Xylocaine 2% Jelly at recommended doses. Phenytoin and other antiepileptic drugs such as phenobarbitone, primidone and carbamazepine appear to enhance the metabolism of lidocaine but the significance of this effect is not known. Phenytoin and lidocaine have additive cardiac depressant …

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. Systemic adverse reactions are rare and may result from high plasma levels due to excessive dosage or rapid absorption, or may result from hypersensitivity, idiosyncrasy or reduced tolerance on the part of the patient. Such reactions are systemic in nature and involve the central nervous system and/or the cardiovascular system. Central nervous system CNS reactions are excitatory and/or depressant and may be characterised by lightheadedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, tinnitus, blurred vision, vomiting, sensation of heat, cold or numbness, twitching, tremors, convulsions, unconsciousness and possibly respiratory …

For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia). Management of Local Anaesthetic Emergencies The first consideration is prevention, best accomplished by careful and constant monitoring of cardiovascular and respiratory vital signs and the patient's state of consciousness after each local anaesthetic administration. At the first sign of change, oxygen should be administered. Treatment If convulsions occur then immediate attention is required for the maintenance of a patent airway and assisted or controlled ventilation with oxygen, via a positive airway pressure delivery system mask. Adequacy of the circulation should then be evaluated, bearing in mind that drugs used to treat convulsions depress the circulation when administered IV. Should convulsions persist despite adequate respiratory support, and if the status of the circulation permits, appropriate anticonvulsant medication such as an ultra-short acting barbiturate or a …

Effects on fertility No data available. Use in pregnancy – Pregnancy Category A Lidocaine crosses the placental barrier and may be taken up by foetal tissues. When used for surface anaesthesia lidocaine blood levels after normal doses are low so little drug is available for placental transfer. There are, however, no adequate and well-controlled studies in pregnant women. Reproduction studies have been performed in rats at doses up 500 mg/kg/day and have revealed no evidence of harm to the foetus caused by lidocaine. It is reasonable to assume that a large number of pregnant women and women of child bearing age have used lidocaine. No specific disturbances to the reproduction process have so far been reported. Use in lactation Lidocaine enters breast milk, but in such small quantities that there is generally no risk of affecting the child at therapeutic dose