Muscarinic Antagonists Flashcards Preview

Pharm Exam 3 > Muscarinic Antagonists > Flashcards

Flashcards in Muscarinic Antagonists Deck (61):
1

Anticholinergic drugs do what?

Antagonists that prevent acetylcholine signaling

2

Antimuscarinic acts where?

Post ganglionic neuroeffector junction to block parasympathetic autonomic discharge

3

Neuromuscular blocker acts where?

Neuromuscular junction to block acetylcholine signaling

4

Ganglionic blockers act where?

They act as antagonists at both parasympathetic and sympathetic autonomic ganglia

5

How do Muscarinic Receptors M1, M3, and M5 signal?

Via increase in intracellular Ca2+and PKC activity

6

Where is M1 located? (3)

CNS
Sympathetic postganglionic cells
Presynaptic sites

7

M3 locations? (3)

Smooth muscle
Lungs
Eyes effector cell membranes

8

M2 and M4 are activated how?

Signal via cAMP decreased and reduced cAMP-dependent PK activity

9

Where is M2 located? (3)

Myocardium
Smooth muscle
Presynaptic sites

10

Where is M4? (1)

CNS

11

Atropa Belladonna (deadly nightshade) gave us what?

Atropine

12

Belladonna causes what effect in the eyes?

Increase in pupil size

13

Antimuscarinic drug use in ocular exams? (2)

Mydyriasis (pupil dilation)
Cycloplegia (Loss of focus/regulation of lens thickness)

14

Which M receptor is being targeted in antimuscarinic drugs?

M3

15

How does Muscarinic antagonists affect incontinence?

Triggers bladder relaxation via M3 receptor which mediates contraction of bladder and M2 which inhibits relaxation

16

Drug used in irritable bowel syndrome to induce GI paralysis and reduce secretions?

Mebeverine

17

What other uses are listed for antimuscarinic drugs? (4)

COPD
Pre-Op Anti-Secretory
Motion Sickness
Parkinson's disease

18

For COPD use what is the effect of muscarinic antagonists? (2)

Reduce secretions
Cause Bronchial dilation

19

In COPD use what would I combine antimuscarinic drugs with?

B-adrenergic agonist

20

What is the purpose of anti-muscarinic in treating Parkinson's?

Adjunct to L-DOPA

21

What is the mechanism of Antimuscarinic drugs?

Competitive and reversible inhibition of muscarinic receptor activation by preventing the binding of Ach.

22

Two classes of antimuscarinic?

Tertiary Amines (Atropine)
Quaternary Amines/Ammonium (Glycopyrrolate)

23

Main use for Tertiary amines?

Ocular and CNS applications

24

Main use of Quaternary Amines/Ammonium?

GI tract and peripheral application

25

What specific tertiary amine do you use for COPD?

Ipratropium

26

Characteristics of tertiary amines? (2)

Can penetrate CNS
Non-selective antagonists

27

Which tertiary amine is better for CNS penetration?

Scopolamine is better than Atropine

28

What happens in low vs high doses of Scopolamine?

Low doses you get drowsiness
High doses you get hallucination

29

Why is Scopolamine not for children?

Toxicity

30

How do you give Scopolamine locally?

Patch form

31

Why is Scopolamine useful in surgery and childbirth?

Can cause amnesia

32

When Scopolamine treatment is stopped what effects can be seen?

Rebound effects which cause overstimulation of vestibular and reticular formation of the vomiting center

33

Short acting tertiary amine used in optical applications?

Tropicamide (0.25 days)

34

What does Tropicamide cause? (2)

Cycloplegia (loss of accommodation)
Mydriasis

35

Types of Urinary Incontinence? (4)

Stress (Leak)
Urge (Nocturia)
Outflow (Retention secondary to obstruction)
Functional (Large volume intake)

36

What do you treat stress incontinence with?

Adrenergic agonist

37

What do you treat urge incontinence with?

Anti-cholinergics

38

What do you treat outflow incontinence with?

Cholinergics for atony
alpha antagonists for obstruction

39

Diabetic neuropathy can cause what two dysfunctions?

1) Diabetic bladder dysfunction
2) Diabetic cystopathy

40

What is diabetic bladder dysfunction?

Overactive bladder leading to urge incontinence

41

What is diabetic cystopathy?

Decreased bladder sensation, increased capacity leading to outflow incontinence

42

How does pregnancy affect the bladder?

Increased weight from baby damages bladder sphincter

43

Effect of Congestive heart failure on bladder?

Retention of water causes more water in body causes too much urine causes nocturia

44

What do muscarinic antagonists do for urinary incontinence? (2)

Suppress involuntary bladder contraction
Increase maximal urine volume that causes involuntary bladder contraction

45

Which muscle in the bladder does M2 handle?

Detrusor

46

Benefit of M3 selective Darifenacin or Solifenacin in urinary incontinence?

Longer acting than oxybutinin

47

Benefit of M2/M3 selective Tolterodine?

Fewer side effects than oxybutinin

48

Downside of Tolterodine?

Too much/too long use can lead to acute urinary retention

49

Quaternary amine probanthine used for what?

Gastric disorders such as GI spasms/peptic ulcers

50

What restricts Probanthine from crossing the gut?

Charged Nitrogen

51

What type of restricted is Probanthine?

Peripherally

52

Main antispasmodics for irritable bowel syndrome? (3)

Atropine
Dicyclomine
Hyoscyamine

53

Who do you avoid giving antispasmodics to?

Glaucoma patients

54

Which muscarinic receptors mediate constriction of bronchial smooth muscle?

M3
So M3 antagonist will block Ach mediated constriction and open the airways

55

M3 antagonists enhance what?

B-adrenergic agonists in COPD

56

What is known as the "rescue inhaler"?

Ipratropium: short acting

57

What is known as the daily inhaler?

Tiotropium: long acting

58

What do tertiary amines for Parkinson's act on?

CNS M1 receptors

59

What is the preferred Tri-cyclic Anti-depressant in elderly to moderate anticholinergic effects ?

Nortriptyline (Aventyl, Pamelor)

60

Important drug in treating Parkinson's?

Trihexyphenldyl

61

When do you not give anti muscarinic drugs? (4)

Glaucoma
Tachycardia
Intestinal obstruction
Urinary obstruction