Brainscape's Knowledge GenomeTM

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


See full index

Pharmacology Exam 2 > Parasympathetic drugs > Flashcards

Parasympathetic drugs Flashcards

1
Q

Effects of ACh on the body

A
  • Skeletal muscle contraction
  • Convulsions in CNS
  • Bladder, uterine contraction
  • Miosis
  • Emesis - GI contraction
  • Bradycardia/bronchoconstriction
  • Increased secretions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Direct acting parasympathomimetics

A
  • Bethanechol (important)
  • Pilocarpine (important)
  • ACh
  • Carbachol (old opthalmic drug)
  • Muscarine (mushroom poison)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Bethanechol mode of delivery

A

by mouth (PO)

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

Bethanechol targets _________ to cause _________

A

Bethanechol targets M3 muscarinic receptors to cause contraction of the bladder/detrussor muscle.

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

When do you use bethanechol?

A

Urinary disorders in which there is bladder atony (no bladder tone). In cases of spinal injury or dysautonomia - malfunction of ANS

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

When do you not use bethanechol?

A
  • Blocked urethra or GI tract (will stimulate both)

- Overdose leads to excessive urination/defecation or eventual bradycardia.

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

What type of drug is bethanechol?

A

Direct acting parasympathomimetic drug acting on the bladder. (M3)

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

Pilocarpine mode of delivery?

A

Topical ophthalmic mediation

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

Pilocarpine is used to stimulate _________

A

Pilocarpine is used to stimulate mitosis (contraction on the pupil)

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

Pilocarpine can be used to treat __________

A

Glaucoma.

Stretching of the iris allows for the aqueous outflow tract to open up, decreasing intraocular pressure.

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

When do you not use pilocarpine?

A

Anterior uveitis or anterior lens luxation.

** it can also be irritating and mitosis can last 2-6 hours or become irreversible during chronic use.

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

What type of drug is Pilocarpine?

A

DIrect acting parasympathomimetic acting on the eye. (Most likely at M5)

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

What does indirect acting parasympathomimetics mean?

A

They impair the function of acetylcholinesterase (anticholinesterases) in which they irreversibly or reversibly bind so that ACh cannot be broken down causing a build up ACh at the synapse.

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

Name 5 reversible indirect acting parasympathomimetics.

A 
Neostigmine
Pyridostigmine
Edrophonium
Physostigmine
Demarcarium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Neostigmine mode of delivery?

A

Mainly injection, sometimes by mouth.

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

What is neostigmine used for?

A

Large animal. Rumen atony, stimulating GI motility in horses, bladder emptying, reverse neuromuscular blockers, and treat myasthenia gravis (not enough ACh receptors for muscle contraction).

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

How fast is the onset of neostigmine and the duration of neostigmine?

A

Onset is 10-30 minutes and duration is 4 hours.

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

What type of drug is neostigmine?

A

Reversible indirect acting parasympathomimetic acting on acetylcholinesterases at smooth/skeletal muscle.

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

Pyridostigmine mode of delivery?

A

By mouth tablet or syrup, or injectable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is pyridostigmine used for?

A

Stimulating GI motility, bladder emptying, reverse neuromuscular blockers, and MAINLY treat myasthenia gravis in small animals (not enough ACh receptors for muscle contraction)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How fast is the onset of pyridostigmne and the duration of pyridostigmine?

A

Onset is about an hour and duration is 8-10 hours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What type of drug is pyridostigmine?

A

Reversible indirect acting parasympathomimetic acting on acetylcholinesterases at smooth/skeletal muscle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Edrophonium mode of delivery?

A

Injectible only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is edrophonium used for?

A

Diagnosis of myasthenia gravis or determining the a myasthenic crisis from a cholenergic crisis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How fast is the onset of edrophonium and the duration of edrophonium?

A

Onset is less than one minute and duration is about 10 minutes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a myasthenic crisis and how can you use edrophonium to test for it?

A

A myasthenic crisis is caused by progression of the disease myasthenia gravis resulting in flaccid paralysis.

To test for this, give edrophonium IV and if muscle function improves, an increase in cholinesterase inhibitors are needed.

27
Q

What is a cholinergic crisis and how can you use edrophonium to test for it?

A

A cholinergic crisis is when a patient is overdosed by cholinesterase inhibitor resulting in flaccid paralysis.

To test for this, give edrophonium IV and if muscle function worsens, a decrease in cholinesterase inhibitors nay be needed.
**Atropine also may be used in a bradycardia emergency after this.

28
Q

What type of drug is edrophonium?

A

Reversible indirect acting parasympathomimetic acting on acetylcholinesterases as a quick onset test of muscle weakness.

29
Q

Physostigmine AND Demarcarium mode of delivery?

A

Topical ophthalmic drugs.

30
Q

What are Physostigmine AND Demarcarium used for?

A

To induce miosis and potentially as a preventative for glaucoma.

**if used systemically for toxicity/narcolepsy be very cautious because drug CAN CROSS BBB

31
Q

When should you not use Physostigmine AND Demarcarium?

A

In cases of anterior uveitis or lens luxation (could trap iris in forward position)

32
Q

How does a carbamate insecticide effect the body?

A

it is a cholinesterase inhibitor (Reversible indirect acting parasympathetic mimetic) which can readily cross the BBB and at a high dose will result in nicotinic excitement and eventual nicotinic blockade.

33
Q

What are examples of irreversible indirect acting parasympatheticomimetics?

A

Echothiophate iodide and Organophosphate insecticides.

34
Q

What is an irreversible indirect acting paarasympathomimetic?

A

Irreversibly binding cholinesterase inhibitor. Bonds are very strong but can technically still be broken unless the agents undergo ‘aging’ and become truly irreversible.

35
Q

Echothiophate iodine mode of delivery?

A

topical ophthalmic drug.

36
Q

What is Echothiophate iodine used for?

A

Echothiophate iodine is used to induce mitosis/treat glaucoma (lasts up to 12 hours).

37
Q

When should you not use Echothiophate iodine?

A

In cases of anterior uveitis or lens luxation (could trap iris in forward position)

38
Q

What are the signs for organophosphate poisoning? DUMBBELS

A

Same as carbamate insecticides but this is truly irreversible.

Diarrhea
Urination 
Miosis
Bradycardia
Bronchoconstriction 
Emesis - increased GI motility
Lacrimation 
Salivation
39
Q

What antidote can be given for organophosphate poisoning?

A

2-PAM/pralidoxime. Pry the OP off of the acetylcholinesterase.

40
Q

Clicker question:
Which of the following drugs is classified as a direct acting parasympathomimetic?

A. Neostigmine
B. Demecarium
C. Bethanechol
D. Edrophonium

A

C. Bethanechol

41
Q

Atropines mode of delivery?

A

Systemically as an injectable and ophthalmically as topical.

42
Q

What is atropine used for systemically?

A

Treat bradycardia/bradyaryhthmia, treat OP toxicity, and treat cholinergic crisis.

43
Q

When do you not use systemic atropine?

A

Pre-existing tachycardia.

Use caution due to decreased urination and also in horses due to possible sensitivity of GI changes.

44
Q

What is so special about rabbits and atropine?

A

Rabbits have endogenous atropinases that can rapidly metabolize atropine.

45
Q

What is atropine used for ophthalmically?

A

Used for mydriasis (can last up to 120+ hours) to reduce pain in the eye from adhesions.

46
Q

When do you not use ophthalmic atropine?

A

Glaucoma is present (would increase IOP), can cause hyper salivation in cats, and can make horses panic due to cyclopegia (blurred vision).

47
Q

What plant is atropine originally derived from?

A

Belladonna plant

48
Q

What are direct acting parasympatholytics?

A

Muscarinic antagonists that prevent the actions of ACh at PSNS target tissues.

49
Q

What are some examples of direct acting parasympatholytics?

A
  • ATROPINE
  • Glycopyrrolate
  • Oxybutynin
  • Tropicamide
  • Aminopentamide
50
Q

Tropicamide mode of delivery?

A

Topical ophthalmic drug or ointment?

51
Q

What is tropicamide used for?

A

Tropicamide is very similar to atropine with a faster onset and shorter duration (12 hours).

Used for mydriasis during an ophthalmic exam or to help healing after cataract surgery by breaking adhesions in a 12 hour cycle (better than atropine which would have the adhesions constantly open for 120+ hours)

**Atropine still better for pain.

52
Q

When should you not use tropicamide?

A

Glaucoma is present.

Also, be careful with cyclopegia (blurry vision) causing panic in horses.

53
Q

What type of drug is tropicamide?

A

Direct acting parasympatholytic drug acting on the eye.

54
Q

Glycopyrrolate mode of delivery?

A

Injectible

55
Q

What is glycopyrrolate used for?

A

Similar to systemic atropine (Treat bradycardia/bradyaryhthmia, treat OP toxicity, and treat cholinergic crisis) as well has hypersialism (excessive salivation)

56
Q

Benefits for glycopyrrolate over atropine

A

Glycopyrrolate is a quaternary compound that does not cross the blood brain barrier and has a slower onset of action/longer duration causing tachyarrhythmias to be less likely.

Also preferred in rabbits, because they don’t metabolize glycopyrrolate as quickly.

57
Q

What type of drug is glycopyrrolate?

A

Direct acting parasympatholytic drug acting on muscarinic receptors of the PSNS.

58
Q

Oxybutynin and Propantheline mode of delivery?

A

By mouth, tablets.

59
Q

What are Oxybutynin and Propantheline used for?

A

Mainly used as a urinary ‘antispasmodic’ a.k.a urinary incontinence. Targets bladder and GI.

60
Q

Differences between Oxybutynin and Propantheline?

A

Oxybutynin more likely to cross BBB than propantheline.

61
Q

What kind of drugs are Oxybutynin and Propantheline?

A

Direct acting parasympatholytics acting on the bladder/GI.

62
Q

What is aminopentamide used for?

A

Not commonly used but approved as an antispasmodic for the GI tract (diarrhea) in cats and dogs.

Direct acting parasympatholytic

63
Q

Clicker question:
Pilocarpine is a nonspecific muscarinic agonist, that makes it what type of drug?

A. Direct acting parasympathomimetic
B. Indirect acting parasympathomimetic
C. Direct acting parasympatholytic
D. Indirect acting parasympatholytic.

A

A. Direct acting parasympathomimetic

Pharmacology Exam 2 (8 decks)

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