Scopolamine is a muscarinic antagonist that acts by blocking muscarinic acetylcholine receptors. Although it is not clear how scopolamine prevents nausea and vomiting due to motion sickness, which statement below best describes the mechanism of action for this drug?
A) Scopolamine prevents communication between the nerves of the vestibule and the vomiting center in the brain by blocking the action of acetylcholine.
B) Scopolamine breaks down acetylcholine in the synaptic cleft, therefore blocking the drug from entering the neuron.
C) Scopolamine causes chloride channels to open causing a subthreshold graded potential in the soma of the cell and, therefore, no action potential is ever generated that may cause motion sickness.
D) Scopolamine works by preventing calcium influx at the axon terminal, therefore preventing the release of neurotransmitter.
E) Scopolamine works on the optic nerve blocking sodium channels so that the sight of motion does not make an individual sick.

Question

Quizplus · Accepted Answer

Scopolamine acts as a muscarinic antagonist, blocking the action of acetylcholine, which can prevent communication between the nerves of the vestibule (part of the inner ear involved in balance) and the vomiting center in the brain, thus helping to prevent motion sickness.

Scopolamine Is a Muscarinic Antagonist That Acts by Blocking Muscarinic