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A sterile, isotonic, preservative free solution containing Atropine Sulphate, Sodium Chloride and Water for Injections.
Atropine is an antimuscarinic alkaloid. It competitively inhibits the actions of acetylcholine and has both peripheral and central actions. It reduces secretions, especially salivary and bronchial secretions, and also reduces perspiration. It has little effect on biliary or pancreatic secretion.
Atropine has an antispasmodic action on smooth muscle and diminishes gastric and intestinal motility. It blocks the responses of the sphincter muscle of the iris and ciliary muscle of the lens to cholinergic stimulation thereby dilating the pupil (mydriasis) and paralysing accommodation (cycloplegia).
Atropine alters cardiac rate, initially slowing the heart rate. However, the dominant effect is tachycardia which occurs with average clinical doses (400-600 micrograms) and is more profound with larger doses.
Atropine has central nervous system (CNS) activity. Average doses (400 microgram - 1 mg) produce stimulation of the medulla and higher cerebral centres, causing mild vagal excitation. Larger doses cause prominent central excitation, blocking the vagus nerve resulting in restlessness, irritability, disorientation, hallucinations or delirium.
Atropine is well absorbed following intramuscular administration and peak plasma concentrations are reached within 30 minutes. Inhibition of salivation occurs within 30 minutes, peaks within 1-2 hours and persists for 4 hours following intramuscular administration. Increased heart rate occurs within 5-40 minutes and peaks within 210 minutes to 1 hour after intramuscular administration. With intravenous administration increased heart rate effect peaks within 2-4 minutes.
Atropine is well distributed throughout the body. It crosses the blood-brain barrier and also the placental barrier. Atropine has a plasma half-life of 2-3 hours. Following intramuscular administration elimination appears biphasic with an initial phase of about 2 hours and a half life in the terminal phase of 12.5 hours or longer.
Atropine is metabolised in the liver to several metabolites and excreted mainly in the urine. Approximately 30-50% of a dose is excreted in the urine unchanged.
May be given as a preanaesthetic medication to reduce salivary secretions, bronchial secretions and to prevent cholinergic cardiac effects such as cardiac arrhythmias, hypotension and bradycardia.
Atropine may be used in the management of patients with acute myocardial infarction and sinus bradycardia who have associated hypotension and increased ventricular irritability. Atropine has been used in conjunction with morphine or other opiates for the symptomatic relief of biliary or renal colic.
Atropine may be administered concurrently with anticholinesterase agents (eg neostigmine, physostigmine) to block the adverse muscarinic effects of these agents following surgery to terminate curarization.
For poisoning by organophosphate pesticides atropine may be used concomitantly with a cholinesterase reactivator such as pralidoxime to reverse muscarinic effects.
Atropine Sulphate Injection may be given by subcutaneous, intramuscular or direct intravenous injection.
Atropine Sulphate Injection should not be added to any intravenous infusion solutions for administration.
Premedication: 300 to 600 micrograms Atropine Sulphate Injection may be given intramuscularly or subcutaneously 30 to 60 minutes prior to induction of anaesthesia. Alternatively 300 to 600 micrograms intravenously may be given immediately before induction of anaesthesia.
Reversal of Competitive Neuromuscular Block: 600 micrograms to 1.2 mg atropine may be given by slow intravenous injection in conjunction with an anticholinesterase agent (eg neostigmine, physostigmine).
Biliary or Renal Colic: 600 micrograms atropine may be given intramuscularly up to three times daily as an antispasmodic to provide symptomatic relief in conjunction with morphine or other opiates.
Organophosphate Poisoning: 1 to 2 mg atropine may be given intravenously. Additional 2-mg doses may be administered intramuscularly or intravenously every 5 to 60 minutes until symptoms subside, and repeated if they reappear. For severe cases 2 to 6 mg may be administered intravenously, with subsequent additional doses of 2 to 6 mg being administered until symptoms subside.
Doses up to 50 mg may be required within the first 24 hours. With severe cases atropine therapy should be withdrawn gradually to avoid sudden recurrence of symptoms. A cholinesterase reactivator (eg pralidoxime) is administered concomitantly.
Premedication: 65 micrograms atropine subcutaneously for premature infants. 100 micrograms for full term infants and 200 micrograms for infants between 6 months to 1 year. In children older than 1 year atropine may be given intramuscularly or subcutaneously at 10 to 20 micrograms/kg.
Atropine Sulphate Injection is contraindicated in patients who have known hypersensitivity to atropine. It is also contraindicated in patients with prostatic enlargement, paralytic ileus or pyloric stenosis. In patients with ulcerative colitis its use may lead to ileus or megacolon.
Patients with elevated ambient temperature should not receive atropine due to the risk of providing hyperpyrexia, especially in children.
Atropine should not be given to patients with closed-angle glaucoma or narrow angle between the iris and the cornea. Atropine should not be given to patients with myasthenia gravis unless extreme caution is used in its administration.
Atropine should be used with caution in geriatric patients and children since they may be more susceptible to its adverse effects.
Atropine should be used with caution in conditions characterised by tachycardia such as thyrotoxicosis, cardiac insufficiency or failure, and in cardiac surgery where it may further accelerate the heart rate.
Atropine may cause mental confusion, especially in elderly or brain damaged patients.
Caution is required in administering atropine to debilitated patients with chronic pulmonary disease, since reduced bronchial secretions may cause inspissation and bronchial plug formation.
Where patients are exposed to high environmental temperatures, atropine should be used cautiously since heat prostration can result.
Category A: Atropine has been used in a large number of pregnant women and women of child bearing age without an increase in the frequency of malformations or other direct or indirect harmful effects on the foetus having been observed. However, proven safety of atropine in pregnancy has not been established. As with all drugs caution is essential in the use of atropine in pregnant women.
Atropine is reported to distribute into breast milk in small quantities. Since some infants can be sensitive to atropine, breast feeding cannot be recommended.
Xerostomia, blurred vision, photophobia, cycloplegia, mydriasis, urinary hesitancy and retention, flushing, tachycardia, palpitations and constipation. These effects may appear at therapeutic or subtherapeutic doses.
Tremor, headache, nervousness, drowsiness, weakness, hyperpyrexia, dizziness, confusion and/or excitement. Anaphylaxis has been reported. Urticarial rash which may progress to exfoliation, and various dermal manifestations have also been reported.
Atropine may cause increased anticholinergic activity when administered concomitantly with other anticholinergic drugs such as phenothiazines, antihistamines, tricyclic antidepressants or butyrophenones.
Atropine sulphate injection has been shown to be incompatible with solutions containing adrenaline hydrochloride, amylobarbitone sodium, ampicillin sodium, chloramphenicol sodium succinate, chlortetracycline hydrochloride, heparin sodium, metaraminol bitartrate, methicillin sodium, nitrofurantoin sodium, novobiocin sodium, oxacillin sodium, sodium bicarbonate, sulphadiazine sodium, sulphafurazole diethanolamine, tetracycline hydrochloride, thiopentone sodium, vitamin B complex with ascorbic acid, warfarin sodium.
There is considerable patient variability in the susceptibility to atropine. Atropine overdosage is characterised by both peripheral and central symptoms. Toxic doses cause tachycardia, rapid respiration, hyperpyrexia, and central nervous system stimulation marked by restlessness, confusion, excitement, paranoid psychotic reactions, delirium, hallucinations and occasionally seizures or convulsions. A rash may appear on the face or upper trunk. In severe toxicity, CNS stimulation may give way to CNS depression, coma, circulatory and respiratory failure and death.
Symptomatic and supportive therapy should be provided. Close monitoring, including ECG monitoring is recommended. Fluid therapy and other standard treatments for shock should be administered. Hyperthermia should be treated with cold packs, mechanical cooling devices or sponging with tepid water. Maintenance of adequate airway is essential, with respiratory assistance if necessary. Urinary catheterisation may be required if the patient is comatose.
The use of physostigmine as an antidote for atropine poisoning is controversial due to the potential for physostigmine to produce severe adverse effects. The use of physostigmine should be reserved for treatment of patients with extreme delirium or agitation, patients with repetitive seizures, patients with severe sinus tachycardia or supraventricular tachycardia or unresponsive extreme hyperthermia. Relative contraindications to the use of physostigmine include asthma, gangrene, cardiovascular disease and mechanical obstruction of the gastrointestinal or genitourinary tract. In such patients physostigmine should only be used where a life threatening emergency occurs.
Diazepam may be administered to control excitement, delirium or other symptoms of acute psychosis. Phenothiazines should be avoided. Delirium, hallucinations and cardiac arrhythmias often respond to physostigmine. Physostigmine will reverse supraventricular tachycardia produced by atropine overdosage. Intravenous propranolol may be useful for treatment of supra-ventricular tachyarrhythmias unresponsive to physostigmine or where physostigmine is contraindicated.
Store below 30°C. Protect from light.
Prescription Medicine
400micrograms in 1mL ampoules 50 pack
600 micrograms in 1mL ampoules 5 pack and 50 pack
1200 micrograms in 1 mL ampoules 50 pack
Baxter Healthcare Ltd
33 Vestey Drive
Mt Wellington
Auckland
27 March 2000