COMPOSITION:
Each ml contains Atracurium Besylate 10.0 mg

PHARMACOLOGY:
Acuron (Atracurium Besylate) is an intermediate acting competitive non-depolarizing, skeletal muscle relaxant for intravenous administration. Non-depolarizing agents antagonize the neurotransmitter action of acetylcholine by binding competitively with cholinergic receptor sites on the motor end plate.
Acuron (Atracurium Besylate) can be used most advantageously if muscle twitch response to peripheral nerve stimulation is monitored to assess degree of muscle relaxation.
As with other non-depolarizing neuromuscular blockers, the time to onset of paralysis decreases and duration of maximum effect increases with increasing Acuron (Atracurium Besylate) doses.
The dose required to produce 95% suppression of the muscle twitch response with balanced anaesthesia is approximately 0.23 mg/kg body weight (0.11 to 0.26mg/kg body weight).
Recovery from neuromuscular block (under balanced anaesthesia) can be expected to begin approximately 20 to 35 minutes after injection and is usually 95% complete in 60 - 70 minutes.
The neuromuscular blocking action of Acuron (Atracurium Besylate) is enhanced in the presence of potent inhalation anaesthetic.
Repeated administration of maintenance doses of Acuron (Atracurium Besylate) has no cumulative effect on the duration of neuromuscular block, and therefore repeat doses can be administered at relatively regular intervals with predictable results. After an initial dose of 0.4 to 0.5 mg/kg body weight under balanced anaesthesia, the first maintenance dose (suggested maintenance dose is 0.08 to 0.10mg/kg body weight) is generally required within 20-45 minutes, and subsequent maintenance doses are usually required at approximately 15-25 minutes intervals.
The pharmacokinetics of Acuron (Atracurium Besylate) is essentially linear within 0.3 to 0.6 mg/kg body weight dose range.
The duration of neuromuscular block produced by Acuron (Atracurium Besylate) does not correlate with plasma pseudocholinesterase levels and is not altered in compromised renal function. The elimination half life is approx. 20 minutes.
Acuron (Atracurium Besylate) is inactivated in plasma via two non-oxidative pathways; ester hydrolysis, catalyzed by non-specific esterases; and Hofmann elimination, a non-enzymatic chemical process.

INDICATION:
Acuron (Atracurium Besylate) can be used,

• As an adjuvant to general anaesthesia.
  
• To facilitate endotracheal intubation.
  
• To provide skeletal muscle relaxation during surgery or ventilation.

DOSAGE AND ADMINISTRATION:

Use in adults:
Acuron (Atracurium Besylate) is administered by intravenous injection. The dosage range for adults is 0.3 to 0.6 mg/kg body weight (depending upon the duration of full block required) and will provide adequate relaxation for about 20 to 35 minutes.
Endotracheal intubation can usually be accomplished within 90 seconds from the intravenous injection of 0.5 to 0.6 mg/kg body weight.
Full block can be prolonged with supplementary doses of 0.1 to 0.2 mg/kg body weight as required. Successive supplementary dosing does not give rise to accumulation of neuromuscular blocking effect.
Spontaneous recovery from the end of full block occurs in about 35 minutes as measured by the restoration of the tetanic response to 95% of normal neuromuscular function.
The neuromuscular block produced by Acuron (Atracurium Besylate) can be rapidly reversed by standard doses of anticholinesterase agents, such as neostigmine (Neo-choline) and edrophonium, accompanied or preceded by glycopyrrolate (Pyrolate), with no evidence of recurarisation.

Use as an infusion in adults:
After an initial bolus dose of 0.3 to 0.6 mg/kg body weight, Acuron (Atracurium Besylate) can be used to maintain neuromuscular block during long surgical procedures by administration as a continuous infusion at rates of 0.3 to 0.6mg/kg body weight/hour.
Acuron (Atracurium Besylate) can be administered by infusion during cardiopulmonary bypass surgery at the recommended infusion rates.

Acuron (Atracurium Besylate) is compatible with the following infusion solutions for the times stated below:

When diluted in these solutions to give Atracurium Besylate concentrations of 0.5mg/ml and above, the resultant solutions will be stable in daylight for the stated periods at temperature of up to 25 C.

Use in children:
The dosage in children over the age of one month is the same as that in adults on body weight basis.

Use in elderly:
Acuron (Atracurium Besylate) may be used at standard dosage in elderly patients. It is recommended, however, that the initial dose should be at the lower end of the range and that it should be administered slowly.
Use in patients with reduced renal and/or hepatic function:
Acuron (Atracurium Besylate) may be used at standard dosage at all levels of renal or hepatic functions, including end-stage failure.

Use in patients with cardiovascular disease:
In patients with clinically significant cardiovascular disease, the initial dose of Acuron (Atracurium Besylate) should be administered over a period of 60 seconds.

CONTRA-INDICATION:
Acuron (Atracurium Besylate) should not be administered to patients known to have an allergic hypersensitivity to the active ingredient.

PRECAUTION / WARNING:
1. Acuron (Atracurium Besylate) should be administered only with adequate general anaesthesia and only by or under the close supervision of an experienced anaesthetist with adequate facilities for endotracheal intubation and artificial ventilation.
2. Caution should be exercised in administering Acuron (Atracurium Besylate) to patients with a history suggestive of an increased sensitivity to the effects of histamine.
3. In common with other non-depolarizing neuromuscular blocking agents, increased sensitivity to Acuron (Atracurium Besylate) may be expected in patients with myasthenia gravis, other forms of neuromuscular disease and severe electrolyte imbalance.
4. Acuron (Atracurium Besylate) should be administered over a period of 60 seconds to patients who may be unusually sensitive to falls in arterial blood pressure, for example those who are hypovolaemic.
5. Acuron (Atracurium Besylate) is inactivated by high pH and so must not be mixed in the same syringe with thiopentone or any alkaline agent.
6. When a small vein is selected as the injection site, Acuron (Atracurium Besylate) should be flushed through the vein with physiological saline after injection.

PREGNANCY AND LACTATION:
In common with all neuromuscular blocking agents, Acuron (Atracurium Besylate) should be used during pregnancy only if the potential benefit to the mother outweighs any potential risk to the foetus.
Acuron (Atracurium Besylate) is suitable for maintenance of muscle relaxation during Caesarean section, as it does not cross the placenta in clinically significant amounts following recommended doses.
It is not known whether Atracurium Besylate is excreted in human milk.

DRUG INTERACTION:
The following drugs potentiate the effect of Acuron (Atracurium Besylate).

• Inhalation anaesthetics:
  Halothane, isoflurane and enflurane.
  
• Antibiotics:
  Aminoglycoside, tetracycline, lincomycin and clindamycin.
  
• Cardiovascular drugs:
  Propranolol, calcium channel blockers and quinidine.
  
• Diuretics:
  Frusemide, mannitol, thiazide and acetazolamide.
  
• Miscellaneous:
  Magnesium sulphate, Ketamine, Lithium salts, trimetaphan and hexamethonium.

SIDE EFFECT:
Atracurium Besylate is well tolerated and produces minimum side effects during extensive clinical trials.

• General - Allergic reactions (anaphylactic or anaphylactoid response).
  
• CVS - Hypotension, vasodilation, tachycardia, bradycardia.
  
• Respiratory - Dyspnoea, bronchospasm, laryngospasm.
  
• Skin - Rash, urticaria.

STORAGE:
Store at temperatures between 2 to 8 C.
Protect from light.

DO NOT FREEZE.
Upon removal from refrigerator to room temperature storage conditions (25 C) use Acuron (Atracurium Besylate) injection within 14 days even if re-refrigerated.
Any unused Acuron (Atracurium Besylate) from opened ampoules should be discarded.

PRESENTATION:
Pack of 5 x 3 ml ampoules.
Pack of 5 x 5 ml ampoules