NPrep
Start practising
RML PRE 2025
Pharmacology
Easy

Symptoms of atropine overdose include?

Appeared in: RML PRE 2025

Explanation

  • Atropine is an anticholinergic drug that blocks the parasympathetic nervous system.
  • This blockade leads to decreased glandular secretions, resulting in a dry mouth.
  • It causes relaxation of the pupillary sphincter muscle, leading to mydriasis (dilated pupils).
  • By blocking the vagus nerve's effect on the heart's SA node, it causes tachycardia (an increased heart rate).

Why Other Options Were Wrong

  • Option A: Hyper salivation and pinpoint pupils (miosis) are classic signs of cholinergic stimulation, the exact opposite of atropine's anticholinergic effects.
  • Option B: Diarrhea and bradycardia (slow heart rate) are effects of parasympathetic (cholinergic) stimulation. Atropine blocks these effects, causing constipation and tachycardia.
  • Option D: Atropine overdose causes anhidrosis (inability to sweat), leading to hyperthermia and hot, dry skin. Sweating is a cholinergic response.

Related Visual

Visual explanation — Related Visual
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacology: Anticholinergic Toxicity as background academic context rather than a clinical decision trigger.
  • Recognizing the anticholinergic toxidrome is a critical nursing skill for early identification and management of poisoning with drugs like atropine, scopolamine, or tricyclic antidepressants.
  • Nursing interventions for a patient with atropine overdose include ensuring a patent airway, monitoring vital signs (especially temperature and heart rate), providing a cooling blanket for hyperthermia, and preparing for potential administration of the antidote, physostigmine, if ordered.
  • What if? If the patient presented with bradycardia, drooling, and pinpoint pupils, the priority nursing action would be to suspect cholinergic poisoning and prepare to administer atropine as an antidote, not withhold it.
How to Approach the Question
  • First, identify the drug in the question: Atropine.
  • Recall the drug's class: Atropine is a classic anticholinergic (or antimuscarinic) agent.
  • Think about the function of the system it blocks: It blocks the parasympathetic nervous system, which is responsible for 'rest and digest' functions.
  • Deduce the symptoms: Blocking 'rest and digest' will cause the opposite effects. Instead of salivation, you get dry mouth. Instead of pupil constriction, you get dilation (mydriasis). Instead of a slow heart rate, you get a fast one (tachycardia).
  • Evaluate the options based on this deduction. Option C (Dry mouth, mydriasis, tachycardia) perfectly matches the expected anticholinergic effects.
  • Eliminate the other options, recognizing them as cholinergic (parasympathetic) effects.
Concept Tested & Keywords
  • Concept Tested: Pharmacology: Anticholinergic Toxicity
  • Stem keywords: atropine, overdose, symptoms
  • Lead-in keywords: include
  • Negative lead-in flag: false

Question ID

QP7xoGRfwhuLqn6wUGFW_Z

Reference Book

E6 Pharmacology Katzung 16e p. 205-207

E6 Robert Boland, Marcia L. Verduin - Kaplan and Sadock's Comprehensive Text of Psychiatry-Wolters Kluwer Health (2024) (pp 1-16525 of 16525) p. 10794-10796

E6 Pharmacology KD Tripathi Essentials 9e Part 1 p. 155-157

Practise the full RML PRE 2025

Attempt every question from this paper in a timed mock, then review the full solution for each one.

Attempt this paperAttempt in the NPrep app

More Drugs acting on Autonomic Nervoys system Questions

More RML PRE 2025 Questions