Drug Biotechnology Multiple Choice Questions on “Drug Concentration and Pharmacologic Response – Antihistamines”.
1. Antihistamine drugs are antagonists for which receptor?
a) H1 receptor antagonist
b) H2 receptor antagonist
c) H3 receptor antagonist
d) H4 receptor antagonist
Answer: a
Clarification: A drug that reduces or eliminates the effects mediated by the chemical histamine. True antihistamines produce a therapeutic effect which will be mediated by negative modulation of histamine receptors. The term antihistamine only refers to H1 receptor antagonists. Antihistamines compete with histamine for binding sites at the receptors. Antihistamine cannot remove the histamine if it is already bound.
2. Which class of antibody is associated with an allergic reaction?
a) IgE
b) IgA
c) IgM
d) IgG
Answer: a
Clarification: Allergies are caused by a hypersensitivity reaction of the antibody class IgE which are located on mast cells in the tissues and basophils in the blood. When an allergen is encountered, it binds to IgE, which excessively activates the mast cells or basophils, leading them to release massive amounts of histamines. These histamines lead to inflammatory responses ranging from a runny nose to anaphylactic shock.
3. If both the parent has allergy how much percentage chance is there that the child will also get an allergy?
a) 20%
b) 48%
c) 70%
d) 100%
Answer: c
Clarification: If both parents have allergies, you have a 70% of having them, if only one parent does, you have a 48% probability. Allergies can be inherited both from mother and father. If the allergy is caused by any defect in Y chromosome then only having a boy baby will have an allergy.
4. If one of the parents has allergy how much percentage probability is there that the child will also get allergy?
a) 20%
b) 48%
c) 70%
d) 100%
Answer: b
Clarification: Allergies are caused by a hypersensitivity reaction of the antibody class IgE which are located on mast cells in the tissues and basophils in the blood. When an allergen is encountered, it binds to IgE, which excessively activates the mast cells or basophils, leading them to release massive amounts of histamines. If both parents have allergies, you have a 70% of having them, if only one parent does, you have a 48% probability.
5. Which of the following enzyme is essential for the conversion of histidine to histamine?
a) Histidine amylase
b) Histidine hydrolase
c) Histidine decarboxylase
d) Histidine phosphorylase
Answer: c
Clarification: Histamine, when released, causes inflammation by increasing vasodilation, capillary permeability, causing smooth muscle contraction, mucus secretion, and parasympathetic nerve stimulation. Occurs primarily in mast cells and basophils.
6. Which of the following histamine receptor increase permeability during inflammation reaction?
a) H1 receptor
b) H2 receptor
c) H3 receptor
d) H4 receptor
Answer: a
Clarification: A drug that reduces or eliminates the effects mediated by the chemical histamine. The term antihistamine only refers to H1 receptor antagonists. H1 receptors mediate an increase in vascular permeability at sites of inflammation induced by histamine. Antihistamine cannot remove the histamine if it is already bound.
7. Which of the following histamine receptor increases the release of gastric acid?
a) H1 receptor
b) H2 receptor
c) H3 receptor
d) H4 receptor
Answer: b
Clarification: Found mainly in the gastric parietal cells, a low level of these cells can be found in vascular smooth muscles, neutrophils, CNS, heart, uterus. These are G protein-coupled receptor. Increases the release of gastric acid. H1 receptors mediate an increase in vascular permeability at sites of inflammation induced by histamine.
8. What causes the side effects of H1 receptor antihistamines?
a) Lack of selectivity of the H1 receptor
b) Lack of selectivity anti-cholinergic activity
c) Due to CNS depression
d) Lack of selectivity of H1 receptor, anticholinergic effect, and CNS depression
Answer: d
Clarification: Associated with the first generation H1-antihistamines and due to their lack of selectivity for the H1 receptor and anticholinergic activity. Side effects are due to CNS depression are sedation, dizziness, tinnitus, blurred vision, euphoria, incoordination, anxiety, insomnia, tremor, nausea/vomiting. Dry mouth/dry cough, Newer second-generation H1-antihistamines are more selective for the peripheral histamine receptors and have far fewer side effects.
9. Which of the following is the first antihistamine?
a) Piperoxan
b) Ethylenediamine
c) Alkylamines
d) Tricyclics
Answer: a
Clarification: Piperoxan is discovered in 1933 by Jeff Forneau and Daniel Bovent while developing a guinea pig animal model of anaphylaxis. They received the Nobel Prize in 1957. Classes of first-generation H1 receptor antagonist antihistamines are ethylenediamines, ethanolamines, alkylamines, piperazines, tricyclics.