Paediatric dose calculator

Maximum dose and typical block doses of local anaesthetic for a child, by weight and age.

For children. Enter the weight and age to see the maximum single dose, and the usual dose for each kind of block. Children are usually asleep when the block is done, so early warning signs of toxicity are hidden: use the lowest dose that works, inject slowly and aspirate often.

Enter a weight to start.

Usual doses for this child

From the joint ESRA/ASRA recommendations for bupivacaine, levobupivacaine and ropivacaine. The volume uses the strength chosen above.

Block	Recommended	For this child
Upper limb nerve blocksAxillary, infraclavicular, supraclavicular, interscalene.	0.5–1.5 mg/kg of bupivacaine or ropivacaine	Enter a weight
Lower limb nerve blocksFemoral, fascia iliaca, sciatic, adductor canal.	0.5–1.5 mg/kg of bupivacaine or ropivacaine	Enter a weight
Fascial plane blocksRectus sheath, TAP, ilioinguinal. Per side: halve it for a block on both sides.	0.25–0.75 mg/kg of bupivacaine or ropivacaine	Enter a weight
Caudal blockCheck that the volume stays under the maximum dose above.	1 mL/kg of ropivacaine 0.2% or (levo)bupivacaine 0.25%	Enter a weight
Spinal anaesthesiaNewborns and infants.	Bupivacaine 1 mg/kg	Enter a weight
Spinal anaesthesiaChildren over 1 year.	Bupivacaine 0.5 mg/kg	Enter a weight
Continuous nerve catheterUse dilute solutions: bupivacaine 0.125% or ropivacaine 0.2%.	0.1–0.3 mg/kg per hour of bupivacaine or ropivacaine	Enter a weight
Epidural infusionUnder 3 months.	No more than 0.2 mg/kg per hour	Enter a weight
Epidural infusion3 months to 1 year.	No more than 0.3 mg/kg per hour	Enter a weight
Epidural infusionOver 1 year.	No more than 0.4 mg/kg per hour	Enter a weight

Maximum single doses used here

Drug	mg/kg	Upper limit
Levobupivacaine	2.5 mg/kg	150 mg
Bupivacaine	2.5 mg/kg	150 mg
Ropivacaine	3 mg/kg	225 mg
Lidocaine (plain)	3 mg/kg	200 mg
Lidocaine with adrenaline	7 mg/kg	500 mg

Actual body weight is used. In an obese child use the ideal weight for height instead.
Under 6 months the maximum is reduced by 30% here: babies have less binding protein and clear amide local anaesthetics more slowly, so more free drug reaches the heart and brain.
All injections add up: the block, any infiltration by the surgeon, and any infusion started afterwards.
Infusions: keep within the hourly limit for the child's age and review after 48 hours, sooner in babies.
Be ready to treat toxicity: see the LAST protocol. For adults use the adult dose calculator.

Sources: Suresh S, Ecoffey C, Bosenberg A, et al. The European Society of Regional Anaesthesia and Pain Therapy/American Society of Regional Anesthesia and Pain Medicine recommendations on local anesthetics and adjuvants dosage in pediatric regional anesthesia. Reg Anesth Pain Med 2018;43:211–216. Lönnqvist PA. Toxicity of local anesthetic drugs: a pediatric perspective. Paediatr Anaesth 2012;22:39–43. Maximum doses are the limits in common paediatric use (bupivacaine and levobupivacaine 2.5 mg/kg). A guide for trained clinicians only: it does not replace clinical judgement, the BNF for Children or your hospital's policy.