Plasma concentration following oral and intramuscular atropine in children and their clinical effects.

In a paediatric population, we compared i.m. v oral atropine premedication to a control group without atropine and determined atropine plasma concentrations (APC). Forty-five children were randomly assigned to one of three groups. Group I received atropine, 20 micrograms.kg-1 i.m., 15 min prior to induction. Group II received atropine, 30 micrograms.kg-1 orally, group III received no atropine. APC (expressed as percent of muscarine-2 receptor subtype occupancy), heart rate, rectal temperature, and salivation were determined before atropine, and 15, 25, 45, 60, 90, 120 (no APC), and 150 min following atropine. Only 10-20% of the M2-cholinoceptors were occupied after oral atropine with a peak…