Available therapies include the use of anticholinergic drugs, speech therapy, prosthetic devices, behavioral therapy, biofeedback, radiation therapy, and a variety of surgical procedures. No single therapy has been documented to resolve sialorrhea satisfactorily in all patients. The drug is a competitive antagonist of the muscarinic actions of acetylcholine. It does not prevent the release of acetylcholine but antagonizes the effect of this neurotransmitter on the effector cells. Atropine-induced inhibition of salivation occurs within 30 minutes to one hour.
Inhibition peaks within two hours after oral administration but can persist for up to four hours.
The usual oral dose for adults is 0.4 mg every 4 to 6 hours. The drug is well absorbed from the small intestine. Peak plasma concentrations occur within one hour. The plasma half-life for atropine sulfate is about 2.5 hours. Nevertheless, one must be aware of a variety of potential adverse effects.