Belladonna alkaloids, tertiary amines
Atropine is a Solanaceae (nightshade) plant alkaloid, a muscarinic receptor antagonist that binds equally to М1, М2, and М3 muscarinic receptor subtypes. Acts on both central and peripheral muscarinic receptors.
As a symptomatic agent in peptic ulcers of the stomach and duodenum, pylorospasm, acute pancreatitis, cholelithiasis, cholecystitis, bowel and urinary tract spasms, bronchial asthma, bradycardia due to increased vagal activity, to decrease the secretory activity of the salivary, gastric, bronchial, and occasionally sweat glands; before radiological examination of the gastrointestinal tract (to lower the tone and motility).
The drug is indicated for use before anesthesia and surgery, during surgery to prevent bronchial and laryngeal spasm. It decreases the secretory activity of glands as well as reflex reactions and undesirable effects due to the activation of the vagus nerve. As a specific antidote in intoxication with cholinomimetic and anticholinesterases (including phosphoorganic) substances.
Atropine sulfate is administered subcutaneously, intramuscularly, intravenously. In induction anesthesia to diminish the risk of vagal heart rate suppression and to decrease the secretion of salivary and bronchial glands, 0.3–0.6 mg subcutaneously or intramuscularly 30–60 minutes before anesthesia; in combination with morphine (10 mg morphine sulfate) 1 hour before anesthesia. In intoxication with anticholinesterase agents, atropine sulfate is administered 2 mg intramuscularly every 20–30 minutes until skin flushing and dryness, mydriasis, tachycardia, and normalization of respiration occur. In moderate to severe poisoning, atropine can be administered for two days (till signs of “over-atropinization” appear).
The highest single dose for children depends on age:
– Under 6 months: 0.02 mg
– 6 months to 1 year: 0.05 mg
– 1 to 2 years: 0.2 mg
– 3 to 4 years: 0.25 mg
– 5 to 6 years: 0.3 mg
– 7 to 9 years: 0.4 mg
– 10 to 14 years: 0.5 mg
The maximum daily subcutaneous doses for adults are: once: 1 mg, daily: 3 mg.
In elderly patients, atropine sulfate should be administered with caution.
In children, the drug should be used in the doses that are specified in the Dosage and administration Section.