& x20;Respiratory depression is NOT a feature of which of the following poisonings? - INI-CET EXAM -2026

INI-CET EXAM -2026

Pharmacology

Medium

Appeared in: INI-CET EXAM -2026

Explanation

Strychnine is primarily a spinal poison, not a central nervous system depressant.
It causes violent convulsions (tetanic spasms) by blocking inhibitory glycine receptors in the spinal cord.
Death occurs from asphyxia due to the spastic paralysis of respiratory muscles, not from direct depression of the respiratory center in the brainstem.

Option A: Gelsemium is a potent central nervous system depressant. Poisoning leads to muscular weakness and paralysis, including the muscles of respiration, causing respiratory failure.
Option C: Opium and its derivatives (opioids) are classic examples of poisons that cause respiratory depression. They act directly on the respiratory centers in the brainstem, decreasing the rate and depth of breathing, which is the primary cause of death in opioid overdose.
Option D: Dhatura (Jimsonweed) contains anticholinergic alkaloids like atropine and scopolamine. In severe poisoning, these can lead to delirium, coma, and paralysis, which can involve the respiratory muscles and cause respiratory failure.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Toxicology and Poisoning as background academic context rather than a clinical decision trigger.
Recognizing the specific toxidrome (pattern of signs and symptoms) is crucial for emergency management. The treatment for strychnine-induced convulsions (benzodiazepines, muscle relaxants) is vastly different from opioid-induced respiratory depression (naloxone).
A key nursing assessment in any suspected poisoning is the patient's respiratory status (rate, depth, effort) and level of consciousness. Pinpoint pupils with respiratory depression strongly suggest opioid poisoning.
What if? If a patient presents with severe muscle rigidity and spasms after an unknown ingestion, the priority is to manage the airway and control the seizures with benzodiazepines, suspecting a convulsant poison like strychnine, rather than administering naloxone which would be ineffective.

How to Approach the Question

First, identify the key negative term in the question: 'NOT'. This means you are looking for the option that is the exception.
The core concept is 'respiratory depression'. You need to evaluate which of the listed poisons does not cause this specific effect.
Recall the primary mechanism of action for each poison class: Opioids (Opium) are classic respiratory depressants. Anticholinergics (Dhatura) and other CNS depressants (Gelsemium) can cause respiratory paralysis.
Consider Strychnine. Its primary effect is on the spinal cord, causing convulsions. This is a different mechanism from central respiratory depression.
Conclude that strychnine causes death by a different respiratory mechanism (asphyxia from muscle spasm), making it the correct answer.

Concept Tested & Keywords

Concept Tested: Toxicology and Poisoning
Stem keywords: Respiratory depression, poisoning
Lead-in keywords: NOT
Negative lead-in flag: The question asks to identify the poison that does NOT cause respiratory depression.

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