Anti-Cholinergics Flashcards

1
Q

What is the Mechanism of action of Atropine?

A

blocks muscarinic ACh receptors

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

what are the main clinical uses of atropine? (there are a lot ~ 5)

A

1) EYES: Used to dilate pupils (mydriasis), to paralyze accommodation reflex (cycloplegia)
2) GI: antispasmodic
3) Urinary Retention
4) HEART: Bradycardia, 2nd degree heart block (mobitz I)
5) organophosphate poisoning

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

Can atropine cross BBB?

A

yes

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

MOA of Antimuscarinics in the Cardiovascular system

A

May block pre-synaptic sites first and increase release of Ach and lower HR. then is works at POST-SYNAPTIC M2 sites on SA node and increases HR

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

MOA of anti-muscarinics on secretions?

A

work at M3 receptors- blocks salivary glands.

produces dry mouth, dry eye (blocks lacrimal and sweat glands)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

MOA of anti-muscarinics on eyes? 2 main effects.

A

M3- topical:

1) Mydriatic (blocks pupillae sphincter muscle)
2) cycloplegic effects (blocks ciliary muscle, loss of accommodation)

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

If you wanted to block secretions for surgery, which receptor would you want the anti-muscarinic to work at?

A

M3

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

In which cases can anti-muscarinics (like atropine) be used as antidote?

A

cholinergic agonists, esterase inhibitors and some mushroom poisonings

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

What is the therapeutic use for Homatropine?

A

EYE: cycloplegic (to temporarily paralyze accommodation), and as a mydriatic (to dilate the pupil)
GI: reduce motility of GI tract (given with histamine H2 receptor antagonist to treat peptic ulcers)

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

What are the 6 antimuscarinics that are tertiary amines?

A

1) atropine
2) scopolamine
3) homatropine
4) tropicamide
5) benztropine
6) darifenacin

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

what are the 2 antimuscarincs that are quaternary ammonium compounds?

A

1) glycopyrrolate

2) ipratropium

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

what are the 4 ganglionic blocking drugs?

A

1) nicotine
2) meccamylamine
3) glycopyrrolate
4) ipratopium

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

What is the therapeutic use of tropicamide?

A

used in eye exams: cycloplegic (to temporarily paralyze accommodation), and as a mydriatic (to dilate the pupil). short acting when applied as eye drops. It is used to allow better examination of the lens, vitreous humor, and retina.

may also be used before or after eye surgery.

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

Adverse effects of antimuscarinics

A
dry mouth
blurred vision
tachycardia
constipation
inhibition of sweating

larger doses:
restlessness, confusion, hallucinations, delerium

children more susceptible to delirum and hallucination (CNS side affects)
patch not approved in children

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

what drug should you give to reverse serious overdose of antimuscarinics?

A

Physostigmine

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

What are the therapeutic uses of Scopolamine?

A

similar to atropine– acts more in CNS and has longer duration of action.

Anti-nausea for motion sickness.
Block memory for surgery

17
Q

higher doses of scopolamine produce what?

A

excitement

18
Q

side effect of scopolamine?

A

blockage of memory formation

19
Q

What are the therapeutic uses of ipratropium?

A

inhalation– used to treat asthma or COPD

nasal spray– rhinitis

20
Q

What are the therapeutic uses of Benztropine?

A

used to reduce the side effects of antipsychotic treatment. No longer recommended to reverse tumors in Parkinsons because it alters balance.

21
Q

What drug can reverse the effects of Donepezil (CNS cholinesterase inhibitor for Alzheim’ers)?

A

Benztropine

22
Q

What are the 5 NT receptors sites important in the vomiting reflex?

A
M1
D2
H1
5-HT3- serotonin
NK1- Substance P
23
Q

What tract in the brain do anti-emetics work on?

A

nucleus tractus solitarius

24
Q

What is the specific MOA of Darifenacin?

A

competitive muscarinic blocker selective at M3 sites

25
Q

What are the therapeutic uses of Darifenacin?

A

used for overactive bladders

26
Q

what is another drug that can be used to help an overactive bladder aside from darifenacin?

A

Mirabegon (Beta-3 agonist)

27
Q

Cholinergics do what to the detrusor muscle of bladder?

A

contraction– void urine

28
Q

adrenergics (beta-3) do what to the detrusor muscle of bladder?

A

relaxed- urine storage

29
Q

What are the therapeutic uses of Glycopyrrolate?

A

1) blocks vagal reflees during intubation
2) blocks drooling in cerebral palsy
3) blocks secretions in stomach to help with peptic ulcers

doesnt cross BBB

30
Q

ganglionic blockers act where?

A

work on nicotinic receptors on ganglia

no selectivity to SNS or PNS and are not physiologically effective as neuromuscular junction antagonists.

31
Q

Nicotine

A
  • when inhaled is absorbed 90% by lungs

Has higher affinity for CNS receptors and at high concentrations will work on ganglia. Ganglionic blockade occurs later (? don’t think I really get whats going on here– sorry)

32
Q

Ganglionic blockers

peripheral muscarinic effects on sweat glands

A

diaphoresis

33
Q

Ganglionic blockers

peripheral muscarinic effects on heart, exocrine glands and smooth muscle

A
bradycardia
ventricular dysrythrmias
torsades des poins
AV blocks
Cardiac arrest
miosis
blurred vision
lacrimation
etc.
34
Q

mecamylamine MOA

A

competitive ganglionic blocker

prevents stimulation of postynaptic receptors by ACh released from presynaptic nerve endings.

35
Q

clinical use of mecamylamine?

A

used for severe hypertension and uncomplicated cases of malignant HTN. Long duration

36
Q

what is the route of administration of mecamylamine and can it cross BBB?

A

orally active and can cross BBB and cause CNS sedation, tremor, abnormal movements and mental changes

37
Q

Big picture effects of ganglion blockers on

1) CNS
2) EYE
3) CV
4) GI
5) GU

A

1) CNS –> sedation, tremor, abnormal mvmt
2) LOss of accomodation, some dilation or mydriasis
3) CV: drop in BP, moderate tachy
4) GI: GI motility reduced, marked constipation
5) GU: urinary retention, impaired sexual function

38
Q

Major (BIG PIC) therapeutic uses for anticholinergics:

1) CNS (3)
2) EYE (3)
3) GI (2)
4) GU (1)
5) Secretions (2)
6) Respiratory (1)
7) CV (1)

A

1) CNS:
atropine vs. poisons (muscarinic agonist poisonis, cholinesterase inhibitors)

benztropine (used in parkinsons to prevent tremors)

scopolamine (motion sickness prevention)

2) homatropin, atropine and tropicamide for eye exams (mydriasis and cycloplegia)
3) atropine, glycopyrrolate (diarrhea)
4) Darifenacin (M3, urge incontinence)
5) atropine, glycopyrrolate (decreased salivation, bronchial secretions for surgery, rhinorrhea, sweating, acids in stomach)
6) ipratropium (bronchial asthma and copd)
7) Atropine (CPR, bradycarida, second degree heart block)