Local Anaesthetic (Amide) Pregnancy: There are no adequate data from the use of lidocaine in pregnant women; lidocaine passes the placenta and animal studies have shown reproductive toxicity. For short term use during pregnancy and at delivery the benefits should be weighed against the risks. Paracervical or pudendal blockade increases the risk of fetal bradycardia/tachycardia, so the fetal heart rate must be carefully monitored. Lidocaine is excreted into human breastmilk in small amounts and use at recommended doses is unlikely to affect the breast-fed child - breast-feeding can be continued.

Lidocaine (IV — Regional Anaesthesia)

Brand names: Xylocaine

This page concerns intravenous lidocaine used for regional anaesthesia (notably intravenous regional anaesthesia / Bier's block) and as a perioperative analgesic adjunct in orthopaedic and trauma care.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Intravenous regional anaesthesia (IVRA) of the upper extremities: usual total dose 3 mg/kg — depending on the procedure and patient factors, 100-200 mg should be used

Route: Intravenous regional anaesthesia via a tourniquet-isolated upper limb (product basis: lidocaine 10 mg/mL solution for injection in pre-filled syringe). The same product is also used for infiltration anaesthesia and peripheral nerve block (intradermal, subcutaneous or submucosal injection, or injection around peripheral nerves) and for IV bolus

Frequency: Single dose per procedure; the dose should be adjusted to the response of the patient, the site of administration and the expected duration of the surgical procedure, using the lowest concentration and smallest dose producing the required effect

Max: IVRA: the maximum single dose should not exceed 200 mg and 3 mg/kg. Infiltration anaesthesia and peripheral nerve blocks: the generally maximum recommended total dose of lidocaine should not exceed 200 mg, but depending on the procedure and patient factors higher maximum doses may be required

Lidocaine should only be used by or under the supervision of doctors with experience of anaesthesia and resuscitative skills, with resuscitation facilities available. Local anaesthesia and peripheral nerve block anaesthesia: usual total dose 3-5 mg/kg. If used intravenously to prevent pain induced by medicinal products upon injection: 10 to 40 mg as a short bolus prior to the painful procedure (this represents less than half of the 10 mL pre-filled syringe, and the excess must be emptied from the syringe before injection; smaller syringes should be considered). This pre-filled syringe presentation is NOT considered suitable for IVRA of the lower extremities, and is not designed for administration with an electronic syringe pump. Proper tourniquet technique specific to the extremity is essential for IVRA, and the tourniquet should not be loosened within 20 minutes of injection. Elderly: doses are calculated individually according to age and body weight, and may need adaptation as cardiac output and hepatic blood flow (and therefore lidocaine clearance) decrease with age. Cardiac or hepatic insufficiency: the dose may need to be reduced by up to a half. Doses may also need reducing in patients in poor general condition or with reduced protein binding capacity (e.g. renal insufficiency, liver insufficiency, cancer, pregnancy).

Paediatric dose

Route: Infiltration anaesthesia and peripheral nerve block (intradermal, subcutaneous or submucosal injection, or injection into the surroundings of peripheral nerves)

Frequency: Single dose per procedure, calculated individually

Max: Not separately stated for children in the retrieved text — doses are calculated individually according to the patient's age, body weight and the nature of the procedure

Children 2-11 years and adolescents 12-18 years: the usual dosage is 3-4 mg/kg body weight for infiltration anaesthesia and peripheral nerve blocks. For calculation, the average age weight is to be considered for overweight children; the required dose should be calculated and the excess emptied from the 10 mL syringe before injection, with slow incremental injections recommended and careful monitoring of the child. Lidocaine should NOT be used in children aged under 2 years (safety and efficacy not established); should NOT be used intravenously in children aged under 12 years because of the safety concern of toxic reaction; and IVRA of the upper extremities should NOT be used in children and adolescents aged under 18 years because of the safety concern of toxic reaction. For IV use to prevent pain induced by medicinal products upon injection, the posology for adolescents 12-18 years is the same as for adults. Verify against a children's formulary before administration.

Dose adjustments

Renal

Patients should be monitored as renal impairment may cause toxic effects due to the accumulation of active metabolites; the dose may need to be adapted because of reduced clearance and increased half-life of lidocaine.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance, to amide-type local anaesthetics, or to any of the excipients

Side effects

Paraesthesia, loss of consciousness, transient neurological symptoms; convulsions (overdose); persistent anaesthesia, paresis, headache with tinnitus and photophobia
Bradycardia; arrhythmia, myocardial depression or possibly cardiac arrest (overdose or inadvertent intravascular injection)
Hypotension, hypertension
Nausea, vomiting; double vision; rash, urticaria, oedema
Allergic reaction, anaphylactoid reactions, bronchospasm and in severe cases anaphylactic shock; methaemoglobinaemia; respiratory depression

Interactions

Simultaneous administration of lidocaine and other class I antiarrhythmics should be avoided because of the risk of serious cardiac adverse effects
Combination with other antiarrhythmic medicinal products such as beta receptor blockers or calcium channel blockers may enhance the inhibitory effect on atrioventricular and intraventricular conduction and on contractility
Caution in patients with coagulopathy or on anticoagulants (e.g. heparin), NSAIDs or plasma substitutes, as accidental injury of blood vessels may lead to serious bleeding
Combination with other local anaesthetics is addressed in section 4.5, whose text was truncated at the source-fetch limit - clinician to check the full section

Clinical monograph

How it works

Lidocaine is an amide local anaesthetic that blocks voltage-gated sodium channels, preventing nerve impulse conduction; systemically it also has analgesic and anti-hyperalgesic effects.

Prescribing in practice

The principal hazard is local anaesthetic systemic toxicity (LAST) — perioral numbness and tinnitus progressing to seizures, cardiac arrhythmia and arrest — so respect maximum doses, use a functioning tourniquet for Bier's block and have lipid emulsion and resuscitation immediately available.
For intravenous regional anaesthesia the tourniquet must not be released prematurely, as sudden systemic release of the agent can precipitate toxicity.
Use with caution and reduced dosing in hepatic impairment, low cardiac output, the elderly and those with conduction defects; avoid in severe heart block.

Monitoring

Monitor ECG, blood pressure, conscious level and for early signs of systemic toxicity throughout administration.

Counselling the patient

Report ringing in the ears, tingling around the mouth, a metallic taste or dizziness immediately.
The tourniquet (cuff) stays inflated for a set time for your safety.
This provides numbness and pain relief for your procedure.

Evidence & guidelines

AAGBI/Association of Anaesthetists guidance on managing severe local anaesthetic systemic toxicity underpins safe intravenous lidocaine use and immediate lipid-emulsion availability.

Reference: AAGBI LAST Guidelines 2010; ASRA Regional Anaesthesia Guidelines; Miller's Anaesthesia; 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).

Curated clinical cross-links plus same-class fallbacks.

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