atracurium

non-depolarizing neuromuscular blocker· Brands: TracriumIV

Mechanism of action

Atracurium is a non-depolarizing neuromuscular blocker that competes with acetylcholine for binding at nicotinic receptors on the motor end plate. This prevents acetylcholine-induced depolarization, resulting in flaccid paralysis of skeletal muscle. It does not cross the blood-brain barrier significantly and has no effect on consciousness or pain perception.

Pharmacokinetics

Atracurium is administered intravenously. It undergoes spontaneous degradation at physiological pH and temperature via Hofmann elimination, as well as ester hydrolysis. This metabolism is independent of hepatic and renal function, making it suitable in organ dysfunction. The onset of action is within 2-5 minutes and duration is approximately 20-35 minutes. It is metabolized to laudanosine and other inactive metabolites, which are excreted renally.

Indications & dosing

Facilitation of endotracheal intubation

Onset of action within 2-3 minutes; duration about 15-30 minutes.

adult · IV: 0.3–0.6 mg/kg single dose · Onset of action within 2-3 minutes; duration about 15-30 minutes.

Maintenance of skeletal muscle relaxation during surgery

Repeat doses as required to maintain neuromuscular blockade.

adult · IV: 0.1–0.2 mg/kg every 20-30 min · Repeat doses as required to maintain neuromuscular blockade.

Continuous infusion for muscle relaxation in intensive care

For mechanically ventilated patients; monitor neuromuscular function and adjust.

adult · IV: 0.3–0.6 mg/kg/h continuous infusion · For mechanically ventilated patients; monitor neuromuscular function and adjust.

Facilitation of endotracheal intubation (pediatric)

Doses may be similar to adults; monitor closely.

pediatric · IV: 0.3–0.6 mg/kg single dose · Doses may be similar to adults; monitor closely.

Contraindications & precautions

Hypersensitivity to atracurium or other benzylisoquinolinium compounds · Do not use in patients with known allergy.
Myasthenia gravis · Increased sensitivity to non-depolarizing neuromuscular blocking agents; prolonged paralysis may occur.
Ensure adequate facilities for artificial ventilation and intubation are available before administration.
Use with caution in patients with cardiovascular disease, as histamine release may cause hypotension.
Use with caution in patients with asthma or a history of allergic reactions, due to the risk of bronchospasm.
Use with caution in patients with neuromuscular disorders such as myasthenia gravis, and monitor neuromuscular function closely.
Monitor for electrolyte disturbances and acid-base imbalances, as these can affect the degree of neuromuscular blockade.

Adverse effects

Hypotensionserious
Skin flushing
Tachycardia
Bronchospasmserious
Anaphylaxisserious
Prolonged neuromuscular blockadeserious

Monitoring, pregnancy & toxicity

Neuromuscular function (train-of-four) · Continuously or before top-up doses
Heart rate and blood pressure · During and after administration
Respiratory status · Until full recovery from blockade
Pregnancy: Use only if clearly needed. Atracurium is a non-depolarizing neuromuscular blocker that crosses the placenta in small amounts. There is insufficient human data to determine safety, but animal studies have not shown teratogenicity. Consider the benefit of adequate muscle relaxation for the procedure against potential risks.
Toxicity: Prolonged neuromuscular blockade leading to respiratory paralysis and apnoea · Maintain airway and provide mechanical ventilation. Administer an anticholinesterase (e.g., neostigmine) with atropine to reverse the block. Monitor for recurarisation.
Toxicity: Hypotension and tachycardia due to histamine release · Support blood pressure with intravenous fluids and, if needed, vasopressors. Administer an antihistamine if clinically significant.

Antidotes & reversal

Neostigmine with glycopyrrolate · Reversal by acetylcholinesterase inhibition plus antimuscarinic; sugammadex does NOT reverse atracurium.

Clinical notes

Reversal of neuromuscular blockade can be achieved with neostigmine (sugammadex does not reverse atracurium; it is specific for rocuronium and vecuronium).

Log in to read the full atracurium monograph

A free account unlocks the complete drug reference, the interaction checker, prescription practice and every other learning tool.

BNF; local formulary