Anticholinergic Drugs Question and Answers

Anticholinergic Drugs  Important Notes

1. Anticholinergic drugs

• They inhibit the muscarinic actions of acetylcholine
• Examples
  • Atropine
  • Scopolamine
  • Propantheline
  • Methantheline

2. Actions of atropine

• • Decreases all secretions
  • Mydriasis of pupil
  • Increased heart rate
  • Bronchial dilation
  • Relieves hypermotility

3. Drugs causing mydriasis

• • Anticholinergic drugs – atropine
  • Adrenergic drugs – ephedrine, phenylephrine

4. Scopolamine/ Hyosine

• • It is an anticholinergic drug
  • Most effective drug for motion sickness
  • Causes sedation

Anticholinergic Drugs Long Essays

Question 1. Classify anticholinergic drugs. Discuss pharmacological actions, uses & adverse effects of atropine. Mention symptoms of atropine poisoning and the line of treatment.

Answer:

Anticholinergic drugs:

• Anticholinergic drugs are agents which block the effects of acetylcholine on cholinergic receptors.

Anticholinergic drugs Classification:

1. Natural alkaloids – atropine, hyoscine.

2. Semisynthetic derivatives.

• Homatropine, atropine mononitrate hyoscine butyl bromide.

3. Synthetic compounds.

• Mydriatics – cyclopentolate.
• Antisecretory – antispasmodics.
  • Quaternary compounds – propantheline.
  • Tertiary amines – dicyclomine, pirenzepine.
• Vasicoselective – Oxybutynin, flavoxate.
• Anti parkinsonian – trihexyphenidyl, biperiden.

Atropine:

• It is the chief alkaloid of belladonna.
• Pharmacological actions.

Atropine Uses:

1. Preanaesthetic medication.
   • Atropine is administered 30 min before surgery.
   • This reduces salivary and respiratory secretions which prevent laryngospasm and bradycardia.
2. As antispasmodic.
   • In diarrhea and dysentery – reduces abdominal pain.
   • Overcomes spasm of the sphincter of Oddi.
   • In nocturnal enuresis – causes urinary retention.
3. As mydriatic and cycloplegic.
   • Used topically during refractory testing.
   • Used in the treatment of iritis, keratitis, and corneal ulcer.
   • Prevents adhesion between the iris and lens or the iris and cornea.
4. In organophosphorus poisoning.
5. In bronchial asthma, peptic ulcer
6. Used in motion sickness.
7. Used during labor to produce sedation and amnesia.
8. Used in myocardial infarction to block vagal bradycardia.
9. Pulmonary embolism – as it reduces reflex respiratory secretions.

Atropine Adverse effects:

• Adverse effects are common.
• It includes blurring of vision, dry mouth, dysphagia, dry skin, fever, constipation & urinary retention.

Read And Learn More: Pharmacology Question and Answers

• High doses lead to atropine poisoning.

Features of atropine poisoning:

• Palpitation.
• Excitement, psychotic behavior, ataxia, delirium, hallucination.
• Hypotension, weak and rapid pulse.
• Respiratory depression.
• Dilated pupil, photophobia, blurring of vision.
• Cardiovascular collapse, convulsions, coma.

Atropine Treatment:

• Ingested poison was removed by gastric lavage.
• Use cold sponging or ice bags to reduce body temperature.
• A drug used is physostigmine – 1 – 3 mg SC or IV, re¬peated 4-6 hourly.
• It antagonizes control and peripheral effects.

Question 2. Discuss atro¬pine. Mention some atropine substitutes and their uses in therapy.

Answer:

Atropine substitutes:

They aim at producing more selective action on certain functions.

Anticholinergic Drugs Short Essays

Question 1. Compare atropine and cocaine.

Answer:

Question 2. Compare atropine and scopolamine.

Answer:

Anticholinergic Drugs Short Answers

Question 1. Homatropine.

Answer:

Homatropine is an atropine substitute that is used on the eye.

• It causes mydriasis & cycloplegia that last for about 6 – 24 hours.
• They have shorter actions.
• It is used in atropine intolerance.
• It is formed to overcome the lack of sensitivity of belladonna alkaloids.

Question 2. Uses of atropine.

Answer:

• As pre-anesthetic medication.
• As antispasmodic
• As mydriatic and cycloplegic.
• In organophosphorus poisoning.
• In bronchial asthma.
• Used in motion sickness.
• Used during labor to produce sedation and amnesia.
• Used in myocardial infarction.
• Pulmonary embolism.

Question 3. Adverse effects of atropine.

Answer:

• Adverse effects of atropine are common. It includes.
• The blurring of vision.
• Dry mouth and skin.
• Dysphagia.
• Fever
• Constipation.
• Urinary retention.

Question 4. Mention atropine substitutes.

Answer:

• Hyoscine butyl bromide.
• Ipratropium bromide.
• Propantheline.
• Glycopyrrolate
• Pirenzepine.
• Homatropine.

Question 5. The rationale of using atropine as pre-anesthetic medication.

Answer:

Atropine is administered 30 minutes before any surgery because.

• It reduces salivary and respiratory secretion.
  • This prevents laryngospasm.
• It prevents bradycardia during surgery.
• It acts as a bronchodilator.
  • This reduces the risk of bronchial asthma related to anaphylactic shock.

Question 6. Enlist six uses of anticholinergic drugs.

Answer:

1. Preanaesthetic medication – to reduce secretions
2. Antispasmodic – in diarrhea and colic
3. Asmydriatric
4. Parkinsonism – reduces tremors and rigidity
5. Organophosphorous poisoning – atropine is used
6. Motion sickness – hyoscine is given 30 minutes before the journey
7. During labor – hyoscine is used to produce sedation and amnesia

Viva Voce:

1. Atropine is used in organophosphorus poisoning
2. Atropine is a CNS stimulant
3. Scopolamine is CNS depressant