Atracurium: Chemical Formula, Presentation, Indications, Mechanism of Action, Dosage, Side Effects, Warnings and Contraindications

Relaxes the muscles in patients undergoing surgery or in patients using artificial respirators.

Atracurium is a muscle relaxant . It must be given by injection or infusion into a vein.

It is administered by a specialist in a clinical setting. This is a non-depolarizing neuromuscular blocking agent with a short duration of action.

Their lack of significant cardiovascular effects and their lack of dependence on good renal function for elimination provide a clinical advantage over alternative non-depolarizing neuromuscular blocking agents.

Chemical formula

  • C65H82N2O18S2.


  • Injectable solution: 10 mg in 1 ml 25 mg in 2.5 ml, 50 mg in 5 ml.


Atracurium besylate is an intermediate-acting non-depolarizing skeletal muscle relaxant that is used as an adjunct to general anesthesia during surgery to aid intubation and experimentally used to treat drug-induced or electrically induced seizures.

Mechanism of action

This is a neuromuscular blocker that binds to cholinergic receptor sites on the motor end plate, thus inhibiting the action of the neurotransmitter acetylcholine. This prevents the action of acetylcholine and can also release histamine and cause hypotension .


Adults and children over 2 years of age, initial treatment dose: 0.4 to 0.5 mg per kilogram of body weight as an intravenous bolus.

In maintenance doses: 0.08 to 0.1 mg per kilogram of body weight.

The first maintenance dose is generally required 20 to 45 minutes after the initial dose.

The maintenance dose should be administered every 15 to 25 minutes under balanced anesthesia, a little longer under anesthesia with isoflurane or enflurane.

Side effects

  • Cardiovascular : changes in heart rate (0.6-2.1%), mean arterial pressure (1.9%), hypotension, at higher doses than recommended (1.9%), systemic changes in vascular resistance, changes in cardiac index, changes in cardiac output, cardiac arrest (0.001%), tachyarrhythmia, at higher doses (5-8%).
  • Dermatological: erythema at the injection site (0.6%), pruritus (0.2%), urticaria (0.1%).
  • Immune: anaphylaxis (rare), immune hypersensitivity reaction (rare).
  • Musculoskeletal: muscle weakness.
  • Neurological: paralysis.
  • Respiratory: laryngeal spasm, wheezing (0.2%). increased bronchial secretions (0.2%), bronchospasm (0.01%), cyanosis (0.001%).

Warnings and Contraindications

  • Hypersensitivity to atracurium products.
  • Hypersensitivity to benzyl alcohol (multidose vials).
  • Do not use vials containing benzyl alcohol (multi-dose vials) in babies.
  • It should be used only by those experts in airway management and respiratory support.
  • Use only under adequate anesthesia as it has no known effect on consciousness, pain threshold, or cerebration.
  • Be prepared to recognize and treat malignant hyperthermia in any patient scheduled for general anesthesia.
  • Consider the benefit-risk ratio for long-term infusion (1 to 10 days) during mechanical ventilation in the intensive care unit.
  • It should not be administered until patients have fully recovered from succinylcholine-induced neuromuscular block.
  • Neuromuscular block can be prolonged in patients with electrolyte disturbances, hypothermia, myasthenia gravis, Eaton Lambert syndrome, amyotrophic lateral sclerosis, respiratory acidosis, and myotonic dystrophy.
  • Patients with pheochromocytoma.
  • Resistance can develop in burn patients
  • Safety has not been established in patients with bronchial asthma.
  • Special caution in patients where substantial histamine release would be detrimental such as significant cardiovascular disease, allergies, and asthma.
  • It will not counteract bradycardia induced by many anesthetic agents or vagal stimulation.

Special concerns

  • Use with caution during labor and when significant histamine release would be dangerous.
  • Safety and efficacy have not been determined during breastfeeding.
  • Children up to 1 month of age may be more sensitive to the effects of atracurium.
  • Atracurium has been shown to be potentially teratogenic
  • No known effect on pain threshold or consciousness; use only with adequate anesthesia.
  • Atracurium crosses the placenta, but no adverse effects on the fetus or newborn have been shown.


It should not be mixed with alkaline solutions such as barbiturate solutions , nor the concomitant use of medications that enhance the neuromuscular blocking action such as volatile anesthetics, certain antibiotics, lithium, magnesium salts, procainamide, quinidine.

Drugs that enhance the effect of atracurium

Some inhalation anesthetics, isoflurane and enflurane increase potency by approximately 35%, halothane has only a marginal effect (20%), there is no information on a possible interaction with sevoflurane or desflurane.

Antibiotics such as aminoglycosides, tetracycline, clindamycin, vancomycin, antiarrhythmic drugs such as lidocaine, procainamide, quinidine, beta-blocker (propranolol). calcium channel blockers like verapamil , diuretics like frusemide, thiazides , acetazolamide, others like magnesium, ketamine, lithium, and quinine.

Medicines that reduce the effect of atracurium

Chronic anticonvulsant treatment such as carbamazepine and phenytoin.