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Local anaesthetic (amide class) Pregnancy: 'Although animal studies have revealed no evidence of harm to the foetus, lidocaine should not be administered during early pregnancy unless the benefits are considered to outweigh the risks. Lidocaine readily crosses the placental barrier after epidural or intravenous administration to the mother. The ratio of umbilical to maternal venous concentration is 0.5 to 0.6. The foetus appears to be capable of metabolising Lidocaine at term. The elimination half life in the newborn of the drug received in utero is about three hours, compared with 100 minutes in the adult. Elevated lidocaine levels may persist in the newborn for at least 48 hours after delivery. Foetal bradycardia or tachycardia (see section 4.4), neonatal bradycardia, hypotonia or respiratory depression may occur.' Breast-feeding: 'Small amounts of Lidocaine are secreted into breast milk and the possibility of an allergic reaction in the infant, albeit remote, should be borne in mind when using lidocaine in nursing mothers.' Fertility: 'No data available'.

Lidocaine / Mepivacaine (Local Infiltration — Plastics)

Brand names: Xylocaine (lidocaine), Scandonest (mepivacaine)

Lidocaine and mepivacaine are amide local anaesthetics used for local infiltration in plastic surgery to provide field anaesthesia for minor procedures and wound work.

Adult dose

Dose: LIDOCAINE ONLY - mepivacaine is NOT covered by this card. Local anaesthesia by percutaneous infiltration with lidocaine hydrochloride 1.0% w/v injection: the SPC prints no fixed volume or mg dose - 'The dosage should be adjusted according to the response of the patient and the site of administration. The lowest concentration and smallest dose producing the required effect should be given.' Printed ceiling: the maximum dose for healthy adults should not exceed 200 mg
Route: Percutaneous infiltration (local infiltration)
Frequency: Not specified in the SPC - dosage is adjusted according to the response of the patient and the site of administration
Max: 200 mg - 'The maximum dose for healthy adults should not exceed 200mg.' The SPC prints no time period, per-kg basis or per-site basis for this figure, and no separate ceiling for children, elderly or debilitated patients, or for adrenaline-containing solutions
SOURCE: UK SPC via eMC - Lidocaine Hydrochloride Injection B.P. 1.0% w/v (product 4781). Section 2: 'Each 1ml of solution contains 1.0% w/v of Lidocaine Hydrochloride B.P.' Section 4.1: 'Lidocaine is a local anaesthetic of the amide group. The injectable form has a wide range of applications for nerve blockade. It can be used by percutaneous infiltration; to block a major nerve plexus such as the brachial; for epidural anaesthesia; for intravenous regional analgesia.' Section 4.2, in full: 'The dosage should be adjusted according to the response of the patient and the site of administration. The lowest concentration and smallest dose producing the required effect should be given. The maximum dose for healthy adults should not exceed 200mg. Children and elderly or debilitated patients require smaller doses, commensurate with age and physical status.' WHAT THIS CARD IS: the SPC's general posology for a plain lidocaine 1.0% w/v injection, applied to percutaneous (local) infiltration, the use this page is named for. WHAT IT IS NOT: (1) MEPIVACAINE IS NOT COVERED - the bundle holds no mepivacaine label for this page, so no mepivacaine dose or ceiling is given; the page's Scandonest (mepivacaine) half is unsourced. (2) Section 4.1 does not name plastic surgery, burns or emergency procedures; it lists percutaneous infiltration, major nerve plexus block (e.g. brachial), epidural anaesthesia and intravenous regional analgesia, but section 4.2 gives no separate regimen for any of them, so none is given (nerve block, epidural and intravenous regional use are not dosed on this card). (3) The SPC lists lidocaine hydrochloride only (section 2); lidocaine with adrenaline is not covered. (4) No volume is stated for any area or procedure, so the card cannot size a dose for a large area; the 200 mg figure is the only numeric limit the label prints. CHILDREN AND ELDERLY: 'Children and elderly or debilitated patients require smaller doses, commensurate with age and physical status' - the SPC gives no paediatric figure, so no paediatric block is stored; section 4.4: 'Lidocaine Injection is not recommended for use in neonates.' The adverse-reactions section (4.8) of the eMC text was truncated at the source-fetch limit just before the reporting paragraph.

Dose adjustments

Renal

The SPC gives no renal dose-adjustment figure. Section 4.2: elderly or debilitated patients require smaller doses, commensurate with age and physical status. Section 4.4: use with caution where elimination is prolonged, e.g. 'hepatic or end renal insufficiency where the metabolites of Lidocaine may accumulate'.

Hepatic

The SPC gives no hepatic dose-adjustment figure. Section 4.2: elderly or debilitated patients require smaller doses, commensurate with age and physical status. Section 4.4: use with caution where elimination is prolonged, e.g. 'hepatic or end renal insufficiency where the metabolites of Lidocaine may accumulate'.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substance, to anaesthetics of the amide type or to any of the excipients listed in section 6.1 (section 4.3)
  • Complete heart block (section 4.3)
  • Hypovolaemia (section 4.3)
  • Not a labelled contraindication but a section 4.4 precaution: use with caution in myasthenia gravis, epilepsy, congestive heart failure, bradycardia or respiratory depression, and where interacting agents (e.g. phenytoin) raise lidocaine availability or prolong its elimination
  • Not a labelled contraindication but a section 4.4 instruction: lidocaine has been shown to be porphyrinogenic in animals and should be avoided in persons suffering from porphyria
  • Not a labelled contraindication but a section 4.4 warning: the effect of lidocaine may be reduced if it is injected into inflamed or infected areas; not recommended for use in neonates

Side effects

  • 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 of hypersensitivity, idiosyncrasy or diminished tolerance; systemic toxicity mainly involves the central nervous system and/or the cardiovascular system (section 4.8)
  • Nervous system: dizziness or light-headedness, nervousness, tremor, circumoral paraesthesia, tongue numbness, drowsiness, convulsions, coma; signs of CNS stimulation may be brief or absent, so the first signs of toxicity may be confusion and drowsiness, followed by coma and respiratory failure (section 4.8)
  • Cardiovascular: hypotension, bradycardia, myocardial depression, cardiac arrhythmias and possibly cardiac arrest or circulatory collapse (section 4.8)
  • Respiratory: dyspnoea, bronchospasm, respiratory depression, respiratory arrest (section 4.8)
  • Hypersensitivity: allergic or anaphylactoid reactions, anaphylactic shock; rash, urticaria, angioedema, face oedema; skin testing for allergy to lidocaine is not considered reliable (section 4.8)
  • Blood: methaemoglobinaemia (section 4.8)
  • Gastrointestinal: nausea, vomiting; ear: tinnitus, hyperacusis (section 4.8)
  • Eye: blurred vision, diplopia and transient amaurosis may be signs of lidocaine toxicity (section 4.8)
  • Spinal anaesthesia (not the infiltration use on this card): transient neurological symptoms; isolated cases of arachnoiditis or cauda equina syndrome (section 4.8)
  • All frequencies are 'not known (cannot be estimated from the available data)' per section 4.8; the section is truncated at the source-fetch limit just before the reporting paragraph

Interactions

  • Cimetidine and propranolol enhance lidocaine toxicity, requiring a reduction in the dosage of lidocaine (both decrease hepatic blood flow; cimetidine also depresses microsomal activity); ranitidine produces a small reduction in lidocaine clearance (section 4.5)
  • Anti-viral agents (e.g. amprenavir, atazanavir, darunavir, lopinavir) and quinupristin/dalfopristin may increase lidocaine levels - quinupristin/dalfopristin should be avoided (section 4.5)
  • Other local anaesthetics or agents structurally related to amide-type local anaesthetics (e.g. anti-arrhythmics such as mexiletine): systemic toxic effects are additive - use with caution; caution advised with class III anti-arrhythmics such as amiodarone (section 4.5)
  • Hypokalaemia caused by diuretics may antagonise the action of lidocaine (sections 4.4, 4.5)
  • Increased risk of ventricular arrhythmia with QT-prolonging antipsychotics (e.g. pimozide, sertindole, olanzapine, quetiapine, zotepine), prenylamine, 5HT3 antagonists (e.g. tropisetron, dolasetron) (section 4.5)
  • Muscle relaxants (e.g. suxamethonium): risk of enhanced and prolonged neuromuscular blockade (section 4.5)
  • Dopamine and 5-hydroxytryptamine reduce the convulsant threshold to lidocaine; narcotics are probably proconvulsants; opioid-antiemetic combinations sometimes used for sedation in children could reduce the convulsant threshold and increase CNS depression (section 4.5)
  • Adrenaline may decrease vascular absorption of lidocaine but greatly increases the danger of ventricular tachycardia and fibrillation if accidentally injected intravenously (section 4.5)

Monitoring

  • Lidocaine should be administered by persons with resuscitative skills and equipment; facilities for resuscitation should be available when administering local anaesthetics (section 4.4)
  • Use the lowest effective concentration and dose (sections 4.2, 4.4)
  • Watch for neurological and cardiovascular signs of systemic toxicity (dizziness, circumoral paraesthesia, tongue numbness, drowsiness, convulsions; hypotension, bradycardia, arrhythmia) (section 4.8)
  • Intramuscular lidocaine may increase creatinine phosphokinase concentrations, which can interfere with the diagnosis of acute myocardial infarction (section 4.4)
  • Injections in the head and neck regions may be made inadvertently into an artery, causing cerebral symptoms even at low doses (section 4.4)

Clinical monograph

How it works

Both reversibly block neuronal voltage-gated sodium channels, halting impulse conduction; mepivacaine has a duration broadly similar to lidocaine and, unlike lidocaine, produces little local vasodilatation.

Prescribing in practice

  • Inadvertent intravascular injection or excessive total dose can precipitate local-anaesthetic systemic toxicity with CNS and cardiovascular collapse, so aspirate before injecting, use the lowest effective dose and keep lipid emulsion available.
  • If a preparation contains adrenaline, avoid infiltration around digits, nose, ears and other end-arterial territories where ischaemia is a concern.
  • Reduce dose in hepatic impairment, the elderly and the debilitated, in whom amide clearance and tolerance are reduced.

Monitoring

Monitor for early signs of systemic toxicity during and after infiltration, particularly when larger volumes are used, with resuscitation equipment to hand.

Counselling the patient

  • Numbness and loss of sensation in the area are expected and wear off over a few hours.
  • Tell the team immediately if you feel dizzy, hear ringing, notice a metallic taste or feel your heart racing.

Evidence & guidelines

Maximum-dose limits and management of local-anaesthetic systemic toxicity with lipid emulsion are established in UK anaesthetic safety guidance.

Reference: AAGBI Local Anaesthetic Toxicity Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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