43. H1 blockers Flashcards Preview

Respiratory > 43. H1 blockers > Flashcards

Flashcards in 43. H1 blockers Deck (17):
1

mechanism of action

REVERSIBLE inhibitors of H1 histamine receptors

2

H1 blockers - reversible or irreversible

REVERSIBLE

3

H1 Blockers are divided to

1st generation
2nd generation

4

1 st generation H1 blockers drugs

1. diphenhydramine
2. dimenhydrinate
3. chlorepheniramine

5

2nd generation H1 blockers- drugs

-ADINE + cetirizine
1. loratadine
2. fexofenadine
3. desloratadine.
4. cetirizine

6

1st generation H1 blockers -used for

1. allergy
2. motion
3. sleep aid

7

2nd generation H1 blockers -used for

allergy

8

1st generation H1 blockers -toxicity

1. sedation
2. antimuscarinic
3. antiadrenergic

9

2nd generation H1 blockers -toxicity

sedation ( much less than 1st generation)

10

1st vs 2nd generation H1 blockers according to sedation (why

2nd generation is Far LESS sedating than 1st generation because of decreased entry into CNS

11

• Are H1 blockers reversible or irreversible inhibitors?

Reversible

12

• Name four second-generation H1 blockers.

Loratadine, fexofenadine, cetirizine, and desloratadine

13

• First-generation H1blockers usually end in ____, whereas second-generation H1blockers usually end in ____.

-en/-ine or -en/-ate, -adine

14

• A patient has motion sickness on a flight and would like to fall asleep. What class of medication would be useful for this patient?

H1 blockers (e.g., diphenhydramine), which are useful for allergies, motion sickness, and as sleep aids

15

• A patient takes chlorpheniramine for allergies. What side effects would you counsel the patient on?

Sedation, antimuscarinic symptoms, anti-α-adrenergic symptoms

16

• What is the clinical use of second-generation H1 blockers?

Allergies

17

• A truck driver has bad allergies. You want to prescribe a histamine blocker. Would diphenhydramine work for him?

No (although it treats allergies, it makes him too sleepy [second-generation H1-blockers are less sedating due to lower CNS activity])