Pharma - Berto - L8 part 2

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Questions and Answers

What is the primary clinical application of Pirenzepine?

Prevention of motion sickness

Treatment of asthma

Reduction of gastric secretion in peptic ulcer patients (correct)

Induction of mydriasis for eye examinations

Which drug is specifically contraindicated for patients suffering from glaucoma due to its potential to increase intraocular pressure?

Oxybutynin

Ipratropium

Tropicamide (correct)

Benztropine

What is a common adverse effect associated with the use of antimuscarinic agents?

Bradycardia

Constipation (correct)

Excessive salivation

Increased secretions

In which situation can antimuscarinic agents act as specific antagonists?

In cases of excessive cholinergic administration Signup and view all the answers

How does Ipratropium primarily exert its therapeutic effects?

Through bronchodilation and reduction of secretions Signup and view all the answers

What central nervous system effects can Hyoscine have at therapeutic doses?

Somnolence and amnesia Signup and view all the answers

What is the primary therapeutic application of Methacholine?

Bronchial challenge test to provoke bronchoconstriction Signup and view all the answers

Which of the following is NOT a side effect associated with cholinomimetics?

Dry mouth Signup and view all the answers

What effect does low-dose nicotine have on the ganglia?

It stimulates the ganglia leading to increased heart rate and gastrointestinal motility. Signup and view all the answers

Bethanechol is predominantly effective on which type of receptors?

Muscarinic receptors Signup and view all the answers

Which of the following is true about ganglioplegic agents?

They were once used as antihypertensive agents. Signup and view all the answers

What is the duration of action for Bethanechol when used subcutaneously?

1 hour Signup and view all the answers

What is a major limitation of choline esters as therapeutic agents?

Their rapid inactivation by acetylcholinesterase. Signup and view all the answers

Which cholinomimetic is commonly used in the treatment of glaucoma through eye drops?

Pilocarpine Signup and view all the answers

Which of the following effects is associated with high-dose nicotine?

Ganglionic blockade leading to low blood pressure. Signup and view all the answers

What contraindication is associated with the use of cholinomimetics?

Asthma Signup and view all the answers

What type of receptor selectivity do direct parasympathomimetic drugs possess?

Poor selectivity between muscarinic and nicotinic receptors. Signup and view all the answers

Which of the following drugs is classified as a cholinergic antagonist?

Atropine Signup and view all the answers

Which adverse effect is commonly associated with ganglion blocking agents?

Dry mouth and urinary retention. Signup and view all the answers

What is a common effect of activating M2 receptors on the heart?

Decreased heart rate Signup and view all the answers

Which drug is known for both muscarinic and nicotinic actions?

Acetylcholine. Signup and view all the answers

Which symptom is associated with nicotinic stimulation during cholinergic syndrome?

Respiratory depression Signup and view all the answers

What is a common therapeutic application of nicotine?

Administered transcutaneously for smoke dependence. Signup and view all the answers

What decreases as a result of cholinergic stimulation on smooth muscle?

Urinary retention Signup and view all the answers

What characterizes the effects of DMPP as a ganglion blocker?

It acts on both autonomic and enteric ganglia. Signup and view all the answers

Study Notes

Ganglia-Acting Drugs Overview

Diverse actions with no therapeutic applications.
Includes stimulants and ganglion blockers.

Stimulants

Stimulate both sympathetic and parasympathetic systems.
Effects include:
- Tachycardia
- Increased blood pressure
- Altered gastrointestinal motility and secretions
- Enhanced bronchial, salivary, and sweat secretions
Nicotine has a significant CNS stimulant effect.

Nicotine

Low doses: Stimulates ganglia, increasing blood pressure, heart rate, peristalsis, and secretions.
High doses: Blocks ganglia, leading to decreased blood pressure, reduced gastrointestinal motility, bladder muscle effects, and respiratory paralysis.
Transdermal use for smoking cessation.

Ganglion Blockers

Act on both autonomic and enteric ganglia, predominantly affecting the sympathetic system.
Formerly used as antihypertensives but replaced by more selective drugs.
Significant side effects include reduced sympathetic and parasympathetic tone, dry mouth, and urinary retention.

Examples of Ganglion Blockers

Hexamethonium
Mecamylamine

Direct Parasympathomimetic Drugs

Comprised of choline esters and alkaloids.
Generally non-selective for muscarinic receptors; leads to numerous side effects.

Choline Esters

Acetylcholine: Acts on both muscarinic and nicotinic receptors; low therapeutic value due to rapid degradation.
Carbachol: Potent, acts on cardiovascular and GI systems; used rarely as eye drops for glaucoma.
Methacholine: More selective for M3 receptors used in bronchial challenges; minimal side effects.
Bethanechol: Selective for muscarinic receptors; used for urinary retention and GI motility issues.

Effects of Choline Esters

Bradycardia and vasodilation reducing blood pressure.
Smooth muscle contractions in urinary and GI tracts.
Miosis and increased exocrine secretions.

Therapeutic Applications of Choline Esters

Cardiology: Acetylcholine and Methacholine for atrial tachycardia.
Gastroenterology: Bethanechol and Carbachol for gastric atony and urinary retention.
Ophthalmology: Acetylcholine and Carbachol in cataract surgery.

Alkaloids

Muscarine: Natural compound affecting muscarinic receptors.
Pilocarpine: Commonly used for glaucoma and xerostomia; stimulates secretions.
Arecoline: Acts on both nicotinic and muscarinic receptors.
Oxotremorine: Synthetic; causes parasympathetic overactivity; treated with atropine.

Cholinergic Syndrome Symptoms

Muscarinic: Miosis, excessive secretion, abdominal pain, bradycardia.
Nicotinic: Fasciculations, respiratory depression, tachycardia, hypertension.

Contraindications for Cholinomimetics

Asthma, bowel obstruction, peptic ulcer, coronary insufficiency.

Cholinergic Antagonists

Include both antimuscarinic and antinicotinic drugs, exhibiting limited specificity.

Antimuscarinic Drugs

Atropine: Leads to mydriasis, bronchodilation, and reduced secretions; CNS effects range from mild excitement to severe toxicity.
Hyoscine (Scopolamine): Causes sedation and prevents motion sickness; crosses the blood-brain barrier easily.
Ipratropium: Primarily bronchodilative; helpful in asthma treatment.
Benztropine: Useful in Parkinson’s treatment.
Tropicamide and Cyclopentolate: Induce mydriasis and are used in intraocular pressure issues.

Effects and Applications of Antimuscarinic Drugs

Useful in motion sickness, ocular conditions, respiratory treatments, GI motility reductions, and genitourinary issues.
Common side effects: dry mouth, constipation, blurred vision, particularly problematic in glaucoma patients.

Nicotinic Drugs Summary

Include ganglion blockers and neuromuscular blockers, influencing various functions and syndromes, notably in Parkinson’s treatment.

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Description

This quiz covers ganglia-acting drugs, focusing on stimulants and ganglion blockers. It explores their actions, effects, and applications, including nicotine's role in the CNS and as a smoking cessation aid. Understand the implications of these drugs on the autonomic nervous system.