The nurse administers a drug that stimulate the parasympathetic nervous system. What physiologic response would indicate that the drug is working?

The correct answer is B: Increased gastrointestinal motility. Stimulation of the parasympathetic nervous system promotes rest and digest functions, including increased gastrointestinal motility. This occurs because parasympathetic activity enhances digestion and absorption of nutrients. Pupil dilation (A) is controlled by the sympathetic nervous system. Vasoconstriction (C) is also mediated by the sympathetic system, which is responsible for the fight or flight response. Increased heart rate (D) is another response caused by sympathetic stimulation to prepare the body for action.