Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 2 Pharmacology > Antihistamines > Flashcards

Antihistamines Flashcards

1
Q

what are the general mechanisms for histamine release from mast cells?

A

cytolytic

noncytolytic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what leads to cytolytic mechanism of histamine release?

A
  1. membrane damage
  2. high levels of drugs (opioids)
  3. mechanical damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what leads to noncytolytic mechanism of histamine release?

A
  1. immune response
  2. non-immunological response from basic polypeptides
  3. displacement of histamine from granules by drugs (morphine, codeine, radiocontrast)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

where are H1 receptors expressed? what is the result of activation?

A
  1. smooth muscle cells (vascular, respiratory, GI)
  2. vascular endothelial
  3. CNS neurons
  4. peripheral sensory nerves

Gq (PLC - IP3 - Ca)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

where are H2 receptors expressed? what is the result of activation?

A

gastric parietal cells
cardiac muscle
CNS neurons

increased adnenylyl cyclase, cAMP / PKA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  1. smooth muscle cells (vascular, respiratory, GI)
  2. vascular endothelial
  3. CNS neurons
  4. peripheral sensory nerves

contain what type of histamine receptor? what is the result of activation?

A

H1

Gq (PLC - IP3 - Ca)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

gastric parietal cells
cardiac muscle
CNS neurons

contain what type of histamine receptor? what is the result of activation?

A

H2

increased adnenylyl cyclase, cAMP / PKA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are some of the physiological functions of histamine in the nervous system?

A

pituitary hormone release
wakefulness
appetite / satiety

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what leads to the vasodilation effect of H1 activation?

A

PLC - calcium - increased eNOS - increased NO - vasodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what leads to the vasodilation effect of H2 activation?

A

AC - PKA - vasodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what leads to the increased vascular permeability / edema of histamine? is it mediated by H1 or H2?

A

PLC - calcium - increased contraction of endothelial cells - disruption of endothelial junctions - increased plasma proteins and fluid leak into tissue

H1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the result of H1 activation in the epidermis?

A

itch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the result of H1 activation in the dermis?

A

pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does H1 activation in the lungs cause?

A

elevated secretion of airway fluid and electrolytes - bronchoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

activation of what histamine receptor type leads to elevated secretion of airway fluid and electrolytes - bronchoconstriction?

A

H1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the results of histamine receptor activation in heart muscle? is this mediated by H1 or H2?

A
  1. increased calcium - positive inotropic
  2. speeds up SA node - positive chronotropic

H2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

antihistamines refer to agents that specifically target what receptor?

A

H1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what drug is a physiological antagonist of the histamine response itself?

A

EPI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the release inhibitor antihistamines?

A

cromolyn, nedocromil

omalizumab

20
Q

what type of drug is omalizumab?

A

monoclonal IgE Ab

21
Q

how do 2nd generation antihistamines differ from 1st generation?

A

2nd gen - more strongly target H1
2nd gen - do not enter brain (reduced lipophilicity)
less sedation

22
Q

how do H1 antihistamines exert their effect?

A

reversibly bind to receptor and stabilize inactive form

23
Q

what are the main adverse effects of first generation H1 antihistamines?

A

CNS - cognitive
muscarinic - anticholinergic (dry)
5-HT - increased appetite and weight gain
alpha - increased dizziness

excitation and seizures

24
Q

chlorpheniramine is used to treat what conditions?

A

allergic rhinitis and allergies

25
Q

diphenhydramine (benadryl) has what effects, physiologically?

A

sedative
antimuscarinic
antimotion

26
Q

what are the therapeutic uses for benadryl?

A

allergic rhinitis
cough suppressant
motion sickness

27
Q

what is the unique feature of pyrilamine?

A

low sedative effects
very little antimuscarinic action
no antimotion activity

28
Q

what is the primary use of hydroxyzine?

A

antiemetic

29
Q

what are the primary uses of meclizine? what makes it different from hydroxyzine?

A

motion sickness, vertigo

less sedating than hydroxyzine

30
Q

what is the primary MOA of promethazine?

A

significant inhibition of alpha adrenergic receptors

31
Q

what are the primary uses of promethazine?

A

antiemetic

anti motion sickness

32
Q

promethazine can also block what receptor type, in addition to H1?

A

D2

33
Q

cyproheptadine can also block what receptor type, in addition to H1?

A

5-HT

34
Q

which drugs have the strongest antiemetic effects?

A

diphenhydramine
promethazine
hydroxyzine
meclazine

35
Q

which H1 antihistamines have the highest sedative effects?

A

diphenhydramines
hydroxyzine
promethazine

36
Q

which antihistamine is the significant alpha adrenergic receptor antagonist? what is the result?

A

promethazine

postural hypotension
dizziness
reflex tach

37
Q

which antihistamine is the significant serotonin receptor antagonist? what are its adverse effects? what can it be used for therapeutically?

A

cyproheptadine

antimuscarinic
increased weight gain

serotonin syndrome

38
Q

what are the drug interactions with antihistamines?

A

MAOIs
opioids, ethanol
anticholinergics

39
Q

azelastine is an antagonist of what receptor?

A

H1

40
Q

which antihistamines have lower sedation profiles and are more useful for people working in jobs that require increased wakefulness?

A

loratidine

fexofenadine

41
Q

why are loratidine and fexofenadine beneficial?

A

less sedation

42
Q

fexofenadine should be avoided with coadministration of what agents?

A

antacids

citrus juices

43
Q

what are the MOAs of cromolyn and nedocromil?

A
  1. stabilize mast cell

2. inhibition of chloride channels in cell membranes

44
Q

what are the therapeutic uses of omalizumab?

A

(chronic) urticaria

asthma

45
Q

what drugs are used for chronic urticaria?

A

doxepin

omalizumab

46
Q

what drug is useful for treating allergic conjunctivitis? what is the MOA?

A

ketotifen

H1 antihistamine with additional mast cell and basophil stabilization

47
Q

ketotifen is used to treat what condition?

A

allergic conjunctivitis?

Year 2 Pharmacology (70 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions