Aminosteroid non-depolarising NMB Pregnancy: Insufficient data; use in pregnancy only if the benefit outweighs the risk. In caesarean section the dose should not exceed 100 micrograms/kg. Excretion in human breast milk is unknown.

Vecuronium bromide

Brand names: Norcuron

Vecuronium is an intermediate-acting non-depolarising aminosteroid neuromuscular blocking agent used to provide muscle relaxation during anaesthesia and to facilitate mechanical ventilation.

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: Tracheal intubation: 80–100 micrograms/kg (0.08–0.1 mg/kg) IV bolus; maintenance 20–30 micrograms/kg

Route: Intravenous

Frequency: Intubation bolus, then maintenance doses given when twitch height recovers to 25% of control (more frequently in children, less frequently in neonates/infants)

Intubating conditions established within 90–120 seconds. After intubation with suxamethonium: 30–50 micrograms/kg, delayed until the patient has recovered from the suxamethonium block. Continuous IV infusion (adults): give a loading intubation dose first, then 0.8–1.4 micrograms/kg/min titrated to twitch response. Elderly: same intubation and maintenance doses as younger adults, but duration of action is prolonged. Overweight/obese (≥30% above ideal body weight): reduce dose using ideal body weight. Higher initial doses of 150–300 micrograms/kg have been used without adverse cardiovascular effects when ventilation is maintained. In caesarean section and neonatal surgery the dose should not exceed 100 micrograms/kg. In patients receiving magnesium sulfate, reduce the dose and titrate carefully to twitch response. Paediatric: adolescents (12–17 y) use adult dose; children (2–11 y) same intubation/maintenance doses as adults (80–100 and 20–30 micrograms/kg) but required more frequently; neonates (0–27 days) and infants — an initial test dose of 10–20 micrograms/kg followed by incremental doses is recommended; insufficient data for continuous infusion in children or for preterm newborns — verify against a children's formulary. Neuromuscular monitoring recommended throughout use.

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 vecuronium bromide, to the bromide ion, or to any excipient

Side effects

Prolonged neuromuscular block / delayed recovery from anaesthesia
Hypersensitivity, anaphylactic and anaphylactoid reactions (occasionally fatal)
Hypotension; circulatory collapse and shock; flushing
Tachycardia
Bronchospasm
Muscular weakness / steroid myopathy after long-term use in the ICU

Interactions

Inhalational (volatile) anaesthetics — potentiate neuromuscular block; give smaller/less frequent maintenance doses or lower infusion rates during procedures longer than 1 hour
Suxamethonium (succinylcholine) — prior use affects vecuronium dosing; delay vecuronium until recovery from the suxamethonium block
Magnesium sulfate — enhances neuromuscular block; reduce vecuronium dose and titrate to twitch response

Clinical monograph

How it works

It competitively antagonises nicotinic acetylcholine receptors at the neuromuscular junction, preventing acetylcholine-induced depolarisation and producing flaccid paralysis.

Prescribing in practice

It causes paralysis without sedation or analgesia, so adequate concurrent anaesthesia or sedation is essential to avoid awareness during paralysis.
Its effect is prolonged in hepatic and renal impairment, and block may be potentiated by aminoglycosides, magnesium, and volatile anaesthetics.
Residual block must be excluded before extubation; reversal can be achieved with sugammadex or an anticholinesterase plus an antimuscarinic.

Monitoring

Monitor depth of neuromuscular block with a peripheral nerve stimulator and confirm adequate recovery before reversal and extubation.

Counselling the patient

Reassure the patient that they will be anaesthetised and unaware while the muscle relaxant is acting.
Advise the team that depth of block is guided by nerve stimulator monitoring.
Note that recovery is confirmed before the breathing tube is removed.

Evidence & guidelines

Vecuronium is an established non-depolarising muscle relaxant in UK anaesthetic practice, with quantitative neuromuscular monitoring recommended to avoid residual paralysis.

Reference: AAGBI; 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).