Chapter 20. Nausea and Vomiting
Which of the following is a true statement regarding nausea and vomiting?
A. Patients with nausea and vomiting experience flushing, bradycardia, and dry mouth
B. Stimulation of the serotonin receptors found in the vestibular apparatus causes nausea and vomiting
C. The chemoreceptor trigger zone is protected from blood-borne toxins by the blood—brain barrier making chemotherapy induced nausea and vomiting rare
D. Visceral vagal nerve fibers are rich in serotonin receptors and respond to GI distention and mucosal irritation, which contribute to nausea and vomiting
Option A: Incorrect. Nausea and vomiting are associated with pallor, tachycardia, and increased salivation.
Option B: Incorrect. Nausea and vomiting, especially when associated with motion sickness, is due in part to stimulation of muscarinic receptors, not serotonin receptors, in the vestibular apparatus.
Option C: Incorrect; the chemoreceptor trigger zone is accessible by both cerebrospinal fluid and blood, making it sensitive to blood-borne toxins such as chemotherapy agents that can cause nausea and vomiting.
Option D: Correct. Visceral vagal nerve fibers are rich in serotonin receptors and result in nausea and vomiting in response to GI distention and mucosal irritation.
The adverse effects of dimenhydrinate include:
A. Salivation, diarrhea, insomnia
B. Dry mouth, constipation, drowsiness
C. Salivation, constipation, insomnia
D. Dry mouth, diarrhea, drowsiness
Option A: Incorrect. Dimenhydrinate does not cause salivation, diarrhea, or insomnia.
Option B: Correct. Dimenhydrinate, which is frequently used to prevent and treat motion sickness, is associated with antimuscarinic adverse effects such as dry mouth, constipation and drowsiness.
Option C: Incorrect. Dimenhydrinate does not cause salivation or insomnia, although it does cause constipation.
Option D: Incorrect. Dimenhydrinate does not cause diarrhea, although it does cause dry mouth and drowsiness.
Which of the following adverse effects is associated with promethazine administered intraarterially?
Option A: Correct. Promethazine is associated with limb gangrene if inadvertently administered intraarterially.
Option B: Incorrect. Promethazine is associated with sedation or lethargy, not insomnia.