Lidocaine (lignocaine)
Maximum 3 mg/kg plain (about 20 mL of 1% in a 70 kg adult) or 7 mg/kg with adrenaline. Know the signs of toxicity.
On this page
Maximum doses
| Preparation | Maximum |
|---|---|
| Plain lidocaine | 3 mg/kg (max 200 mg) |
| With adrenaline | 7 mg/kg (max 500 mg) |
1% = 10 mg/mL; 2% = 20 mg/mL. A 70 kg adult can have about 20 mL of plain 1% lidocaine.
Common uses
- Wound infiltration before suturing.
- Ring (digital) block: 2–3 mL of plain 1% each side.
- Haematoma block for wrist fractures: about 10 mL of 1%.
- Lidocaine 2% gel before urinary catheterisation.
Toxicity
Tingling lips, metallic taste, dizziness, confusion, fits, arrhythmias, cardiac arrest. Stop, call for help, support the airway, treat fits; lipid emulsion (Intralipid 20%) for severe toxicity.
Frequently asked questions
How many mL of 1% lidocaine can be given?
Up to 3 mg/kg: about 20 mL for a 70 kg adult (plain), more with adrenaline.
Used in these guides
- Ascitic tap and paracentesis
- Fractures and dislocations: the essentials
- Hand and finger injuries
- Insect bites, stings and scorpions
- Lacerations and wound closure
- Lumbar puncture
- Nosebleed (epistaxis)
- Paronychia and finger infections
- Pleural aspiration and chest drain
- Pleural effusion
- Pneumothorax
- Priapism
- Shoulder injuries
- Skin abscess
- Urinary catheterisation
- Urinary retention
- Wrist injuries
Sources
Doses on this page are typical doses from the sources above. Always confirm with a current drug reference, the product leaflet and your hospital protocol, especially in children, pregnancy and kidney or liver disease.
For FCPS Part 1
Revising for FCPS Part 1? Lidocaine is covered in our textbook chapter Anaesthetics and muscle relaxants, with practice MCQs.