NR293: Antihistamines and Decongestants
(Chapter 36) Questions and Answers Latest
Update
What is the function of anticholinergics? Ans: Block the PNS
Side effects:
No see
No pee
No spit
No sh*t
What is the function of cholinergics? Ans: Salivation
Lacrimation
Urination
Diarrhea
GI distress
Emesis (vomiting)
What is a common cold caused by and what does it do? Ans: Most caused by
viral infection (rhinovirus or influenza)
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Virus invades tissues causing upper respiratory infection.
What is the treatment for the common cold? Ans: Treat the symptoms
Empiric therapy
What is the function of antihistamines? Ans: Prevents/relieves symptoms of
allergies; blocks effects of histamine on target tissues.
Competes with histamine for specific receptor sites.
"The first one there wins!"
What are the two types of histamine receptors? Ans: H1: Mediates smooth
muscle contraction and dilation of capillaries.
H2: Acceleration of HR and gastric acid secretion.
H2 antagonists/blockers/antihistamines complete with histamine for H2
receptors.
What are nonsedating/peripherally-acting antihistamines? Ans: Work
peripherally to block the actions of histamine.
Fewer CNS adverse effects (e.g. sedation).
Longer duration of action leads to increased compliance.
Examples: Loratadine (Claritin), fexofenadine (Allegra),
cetirizine (Zyrtec)
What are the indications for antihistamines? Ans: Allergy: Nasal allergies,
seasonal or perennial allergic rhinitis (hay fever), allergic reactions.
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