Histamine and Histamine Antagonists MCQs
1. In addition to mast cells, histamine is stored within which type of white blood cell?
a. Basophil.
b. Monocyte.
c. Neutrophil.
d. Phagocyte.
2. Which histamine receptor produces effects in the gastrointestinal system?
a. H1.
b. H2.
c. H3.
d. H4.
3. Which toxic effect of histamine is most likely to lead to death, if untreated?
a. Dyspnea.
b. Headache.
c. Histamine shock.
d. Cutaneous flushing.
4. Which is the correct mechanism of action of histamine antagonists?
a. Inhibit the breakdown of histamine.
b. Decrease the production of histamine.
c. Compete with histamine for receptor sites.
d. Block the release of histamine from mast cells and basophils.
5. The sedative effects of antihistamines are produced where?
a. CNS.
b. Periphery.
c. Respiratory system.
d. Gastrointestinal system.
6. In which case is a H1 antihistamine of little value?
a. Acute urticaria.
b. Seasonal hay fever.
c. Anti-motion sickness.
d. Systemic anaphylaxis.
7. In general, of the first-generation antihistamines, which H1 antihistamine drug group produces the fewest sedative effects?
a. Alkylamines.
b. Phenothiazines.
c. Ethanolamines.
d. Ethylenediamines.
8. Which drug was first discovered capable of blocking the H2 receptor?
a. Ranitidine.
b. Metiamide.
c. Cimetidine.
d. Burimamide.
9. Superior drugs have replaced H2 antihistamines in which condition?
a. Gastroduodenal ulcers.
b. Upper gastrointestinal bleeding.
c. Symptomatic relief of acid indigestion.
d. Prevention of gastric aspiration in general anesthesia.
10. Which is a suspected, but not proven, adverse effect of cimetidine?
a. Minor CNS symptoms.
b. Occurrence of gastric cancer.
c. Reversible endocrine symptoms.
d. Increased blood concentrations of specific drugs.
