A nurse is teaching a group of nursing students about antihistamines. Which statement by a student indicates an understanding of the mechanism of action of the antihistamines?
a. "Antihistamines block H1 receptors to prevent actions of histamine at these sites."
b. "Antihistamines block release of histamine from mast cells and basophils."
c. "H1 antagonists can bind to H1 receptors, H2 receptors, and muscarinic receptors."
d. "First-generation antihistamines are more selective than second-generation antihistamines."
ANS: A
Antihistamines block H1 receptors to prevent the actions of histamine. They do not block the release of histamine. H1 antagonists do not bind to H2 receptors; they do bind to muscarinic receptors. Second-generation antihistamines are more selective than first-generation antihistamines.
You might also like to view...
A nurse is assessing a newborn who is jittery, diaphoretic, and hypothermic, and has poor feeding. What laboratory value would the nurse correlate with this condition?
A. Bilirubin: 5 mg/dL B. Blood glucose: 32 mg/dL C. Hematocrit: 50% D. White blood cell count: 25,000/mm3
The nurse is planning to inspect a patient's apical heart impulses. What should the nurse do to ensure that this body organ is optimally assessed?
A) Use perpendicular lighting. B) Use tangential lighting. C) Focus a penlight on the patient's chest. D) Assist the client to a standing position.
When transferring a patient to another unit, you should
A. leave the chart and medications on the desk and return to your unit. B. place all the patient's belongings on the desk and return to your unit. C. give the chart and medications directly to the nurse. D. obtain the patient's vital signs after you have put her to bed.
The nurse is reinforcing teaching for a patient who has upper abdominal pain and is scheduled for an upper gastrointestinal (GI) series
Which of the following statements by the patient would indicate a correct understanding of the teaching? a. "It is an estimated rectal cholangiopancre-atophonography." b. "It is a sigmoidoscopy with radiography after injection of dye." c. "It is an x-ray of the esophagus, stomach, and duodenum using barium." d. "It is a scope inserted into the duodenum with dye injection."