Muscarinic Agonists and the Parasympathetic Nervous System

93 Questions

Muscarinic Agonists target the Parasympathetic Nervous System.

True

Halt Digestion, Mydriasis, Urinary retention, Bronchodilation, and Halt salivary secretions are associated with the Parasympathetic Nervous System.

False

Which of the following is a Reversible Cholinesterase Inhibitor that does NOT cross the blood-brain barrier?

Neostigmine

Which of the following is a Reversible Cholinesterase Inhibitor that does cross the blood-brain barrier?

Donepezil

An overdose of cholinergic drugs is called "Cholinergic Crisis" or "Cholinergic Toxicity".

True

Which of the following ADR is associated with cholinergic agonists?

Bradycardia

Which of the following is the Pharm. Action of Cholinesterase Inhibitors?

Increase duration and amount of synaptic ACh

What is the CNS pathology of Alzheimer's Disease (AD)?

Degeneration of basal forebrain pathway neurons

What is the main symptom of Alzheimer's Disease?

Memory loss

Which pharmacologic class is associated with Alzheimer's Disease?

Cholinesterase Inhibitors

Irreversible, cholinesterase inhibitors that do not cross the BBB are used to treat AD.

False

Rivastigmine is metabolized by cholinesterase.

True

Transdermal patches are available for Donepezil and Rivastigmine

True

Donepezil and Galantamine are substrates of which two CYPs?

CYP3A4/CYP2D6

Irreversible cholinesterase inhibitors are used as pesticides and warfare agents?

True

Which of the following drugs are NOT pesticides?

Tabun

Which of the following drugs is NOT a warfare agent?

Chlorpyrifos

Which pharmacologic class is associated with Myasthenia Gravis (MG)?

Cholinesterase Inhibitor

What is the Peripheral pathology of MG?

Auto-antibodies to muscle-type nicotinic receptors

Muscle weakness and fatigue are symptoms of Myasthenia Gravis (MG).

True

Reversible, competitive cholinesterase inhibitors that do NOT cross the BBB are used to treat MA, Cholinergic crisis from exposure to irreversible cholinesterase inhibitors and Neuromuscular blockade reversal

True

Which cholinesterase inhibitors used for Myasthenia Gravis treatment have a long duration?

Both C and D

What is the most common cholinesterase inhibitor used for Alzheimer's Disease?

Donepezil

Edrophonium, used to treat Myasthenia Gravis, has a short duration (minutes)

True

Antidote, used to treat toxic exposure to irreversible cholinesterase inhibitors (aka Cholinergic Criss or Toxicity). It is an Acetylcholinesterase Activator

Pralidoxime

Parasympathetic Nervous System - Associated with Miosis, Promoting salivary secretions, Maintain steady heart rate, Promote digestion, Promote urination.

True

Cholinergic agonist binds both nicotinic and muscarinic receptors

True

Which of the following drugs are Cholinergic Agonists?

Both A and B

What is the Pharm. Action of Pilocarpine?

Induce miosis and decrease intraocular pressure

What is the MOA of Pilocarpine?

Muscarinic Agonist

What is the clinical use of Pilocarpine?

Glaucoma, ocular hypertension, eye procedures

What is the therapeutic class of Pilocarpine?

Miotic

What is the indication for Methacholine, a Muscarinic Agonist?

Bronchoprovocation Test (bronchial hyperactivity diagnostic tool)

What is the Pharm. Action of Methacholine?

Bronchoconstriction

What is the indication of Bethanechol, a Muscarinic Agonist?

Urinary retention (related to surgical procedure or childbirth)

What is the Pharm. Action of Bethanechol?

Contract bladder detrusor (promote urination)

Match the Muscarinic Agonists with their Pharm. Actions.

ADR = SLUDGE-DDUMBELS Pilocarpine = Induce miosis/lower intraocular pressure Methacholine = Bronchoconstriction Bethanechol = Promote urination

What is the MOA of Atropine?

Muscarinic Antagonist

Which of the following is NOT an indication for Atropine?

Motion sickness (Vertigo)

Atropine indications are usually critical conditions.

True

Atropine is used for Peripheral uses

True

What is the MOA of Scopolamine?

Muscarinic Antagonist

What is NOT an indication for Scopolamine?

GI distress disorders

Scopolamine is indicated for usually NOT critical conditions.

True

Scopolamine is for Central uses.

True

Which of the following is NOT indicated for both Atropine and Scopolamine?

Increasing terminal secretions (salivation, bronchial secretions)

ADRs associated with Atropine and Scopolamine are SLUDGE-DDUMBELS?

False

Which drug does NOT have the "Mydriatic, Cycloplegic" therapeutic class?

Scopolamine

What is the clinical use of the Mydriatic, Cycloplegic class?

Eye procedures (Pupil dilation, Induce Cycloplegia)

What is the Pharm. Action of the Mydriatic, Cycloplegic class?

Induce mydriasis (pupil dilation) or cycloplegia (paralyze muscles that control pupil diameter).

The ADR for the Mydriatic, Cycloplegic class is: Minimized due to local application

True

Which of the following is NOT an non-selective Muscarinic Antagonist for OAB?

Darifenacin

Which of the following is a M3-selective Muscarinic Antagonist for OAB?

Both A and B

Which kind of drugs treat an overactive bladder (OAB)?

Genitourinary/Urinary Antispasmodic

What is the MOA of Genitourinary/Urinary Antispasmodic drugs?

Muscarinic Antagonists

What is the Non-selective OAB drug that can cross the BBB?

Oxybutynin

Darifenacin is a CYP2D6 substrate.

True

Trospium is a CYP3A4 substrate.

False

Trospium has lipophilicity.

False

What is the Pharm. Action of Urinary Antispasmodics?

Bladder detrusor muscle relaxation

What is the MOA of Bronchodilators?

Muscarinic Antagonists

What is the short-acting (6-8 hours) Bronchodilator?

Ipratropium

Which of the following is NOT a long-acting (>12 hours) Bronchodilator?

Ipratropium

What is the Pharm. Action for Bronchodilators?

Induce bronchodilation and reduce bronchial secretions

ADR for Bronchodilators: Xerostomia but minimized due to local application - Anticholinergic Syndrome-like symptoms for systemic circulation.

True

What is the indication for Bronchodilators?

Respiratory disorders

Long-acting muscarinic agonists (LAMA) - Prophylactic use for daily maintenance

True

Which of the following Bronchodilators do NOT have Dry Powder formulations?

Ipratropium

For the Dry Powder Bronchodilators, avoid use if you have a milk allergy

True

What is the Pharmacologic Class for Nicotine?

Nicotinic Agonist

What is the indication for Nicotine?

OTC Smoking cessation aid

Tobacco is the unnatural source of nicotine

False

What is the Pharm. Action of Nicotine?

Decrease nicotine craving and withdrawal symptoms

Match the ADRs of Nicotine

CNS = Psychoactive stimulation CV = Hypertension, Tachycardia Other = Physical/Psychological dependence Binds all 3 nicotinic receptor subtypes: = Nm, Nn, Ng

Match the Positive/Negative effects of nicotine

Positive = Anxiolytics Negative = Gastrointestinal distress Negative = Hyopthermia Positive = Cognitive enhancement

What drug is apart of the Partial Nicotinic Agonist class?

Varenicline

What is the indication for Varenicline?

Rx smoking cessation aid

What is the Pharm. Action of Varenicline?

Decrease nicotine craving and withdrawal symptoms

Which of the following is NOT an ADR to Varenicline?

Increased migraines/Light sensitivity

What Pharmacologic class is Mecamlyamine?

Nicotinic Antagonist

Mecamylamine is in the antihypertensive class, therefore making it indicated for malignant hypertension.

True

What is the MOA of Mecamylamine?

Ganglionic nicotinic antagonist (blocker)

Mecamylamine significantly decreases blood pressure

True

ALL anticholinergics are identified to be inappropriate for any individual with dementia, cognitive impairment, delirium, lower urinary tract symptoms, and benign prostatic hypertrophy

True

Anticholinergic drugs are known as "Antimuscarinics" and "Muscarinic Antagonists"

True

What identifies drugs with increased incidence of anticholinergic syndrome-like adverse drug reactions?

Magellan Anticholinergic Risk Scale

You should avoid taking more than 2 anticholinergic drugs

True

Match the Generic/Brand names

Acetylcholine = Miochol-E Carbechol = Miostat Pilocarpine (ophthalmic) = Isopto Carpine Pilocarpine (oral) = Salagen

Match the Generic/Brand names.

Cevimeline = Evoxac, Tarceva Bethanechol = Duvoid, Urecholine Methacholine = Provocholine Atropine = Atropen

Match the Generic/Brand names.

Scopolamine = Transderm Scop Ipratropium = Atrovent Ipratropium w/ Albuterol = Combivent Tiotropium = Spiriva

Match the Generic/Brand names.

Oxybutynin (oral) = Ditropan Darifenacin = Enablex Donepezil = Aricept Oxybutynin (transdermal film) = Oxytrol

Match the Generic/Brand names.

Solifenacin = Vesicare Tiotropium = Spiriva Tolterodine = Detrol Atropine = Isopto Atropine

Match the Generic/Brand names.

Varenicline = Chantix Mecamylamine = Inversine Nicotine = Nicotine Polacrilex Pralidoxime = 2-PAM

Study Notes

Parasympathetic Nervous System

Targets of Muscarinic Agonists
Associated with:
- Halt Digestion
- Mydriasis
- Urinary retention
- Bronchodilation
- Halt salivary secretions
- Miosis
- Promoting salivary secretions
- Maintaining steady heart rate
- Promoting digestion
- Promoting urination

Cholinergic Crisis

An overdose of cholinergic drugs is also known as "Cholinergic Toxicity"
Associated with cholinergic agonists

Alzheimer's Disease (AD)

CNS pathology:
Main symptom:
Associated pharmacologic class:
Irreversible, cholinesterase inhibitors that do not cross the BBB are used to treat AD
Rivastigmine is metabolized by cholinesterase
Transdermal patches are available for Donepezil and Rivastigmine
Donepezil and Galantamine are substrates of CYP2D6 and CYP3A4

Myasthenia Gravis (MG)

Associated pharmacologic class:
Peripheral pathology:
Symptoms: muscle weakness and fatigue
Reversible, competitive cholinesterase inhibitors that do NOT cross the BBB are used to treat MG
Cholinergic crisis from exposure to irreversible cholinesterase inhibitors and Neuromuscular blockade reversal
Edrophonium, used to treat MG, has a short duration (minutes)

Cholinesterase Inhibitors

Pharm.Action:
Irreversible cholinesterase inhibitors are used as pesticides and warfare agents
Antidote, used to treat toxic exposure to irreversible cholinesterase inhibitors (aka Cholinergic Crisis or Toxicity), is an Acetylcholinesterase Activator