HISTAMINE RECEPTOR ANTAGONISTS HIGH YIELD

Question 1

what are the types?

Answer 1

physiological antagonist
-epinephrine
-anaphylaxis treatment
release inhibitors
HI antagonist
H2 antagonist

Question 2

what are the examples of physiological antagonists?

Answer 2

epinephrine

anaphylaxis treatment

Question 3

what are the examples of release inhibitors?

Answer 3

cromolyn

nedocromil

Question 4

name this histamine antagonist?

allergy, cold medicine, sleep aids, motion sickness, antiemetic

1st and 2nd generation H1 antagonists

Answer 4

HI antagonist

Question 5

name this histamine antagonist?

peptic ulcer disease, GERD, ulcer prophylaxis, heartburn

famotidine, cimetidine, ranitidine

Answer 5

H2 antagonist

Question 6

what are examples of first generation antihistamines?

Answer 6

diphenhydramine
hydroxyzine
meclizine
promethazine
cyproheptadine
brompheniramine
chlorpheniramine

Question 7

what are examples of second generation antihistamines?

Answer 7

fexofenadine (allegra)
loratadine (Claritin)
cetirizine (zyrtec)
desloratadine (clarinex)
levocetirizine (Xyzal)

Question 8

name this generation antihistamine?

more sedation
-more lipophilic

well absorbed
-peak 1-2 hours

shorter acting
-4-6 hrs per dose

more side effects

sedating

more anti-ACh effects

Answer 8

1st generation

Question 9

name this generation antihistamine?

much less sedation
-less lipophilic

well absorbed

longer acting
-12-24 hours

less side effects

little/no sedation

much less anti-ash effects

Answer 9

2nd generation

Question 10

what are the therapeutic uses?

Answer 10

allergies and allergic reactions

motion sickness and vestibular disturbances

nausea and vomiting

anxiety

sleep aids

cyproheptadine

Question 11

MOA against allergies and allergic reactions?

Answer 11

antagonizes histamine effects on smooth muscle, blood vessels, immune cells

also blocks muscarinic receptors (1st gen>2nd gen)

Question 12

MOA against motion sickness and vestibular disturbances?

Answer 12

antimuscarinic effects-suppresses vestibular end-organ receptors and inhibits activation of central cholinergic pathways

Question 13

used for nausea?

Answer 13

doxylamine (PO)
combined with Vit B6
preferred in pregnancy

Question 14

used for anxiety?

Answer 14

hydroxyzine (PO,IM)
generalized anxiety
adjunct in organic disease states in which anxiety is manifested

Question 15

used for sleep aids?

Answer 15

doxylamine

diphenhydramine

Question 16

unique antihistamine because it has anti serotonergic activity

no longer used for allergies

off label use for treating decreased appetite secondary to chronic disease

Answer 16

cyproheptadine

Question 17

adverse effects and toxicity?

Answer 17

anti-cholinergic effects
-sedation
-dry mouth
-blurred vision
-urine retention
-GI upset
excitation and convulsions in children
postural hypotension (promethazine)