Which sign indicates CNS depressant toxicity requiring prompt assessment?

• A. Increased heart rate and tremor
• B. Nausea
• C. Slurred speech and ataxia
• D. Clear and alert mental status

Answer: (C)

Slurred speech and ataxia show that the brain’s depressant effects are impairing motor control and speech, which points to CNS depressant toxicity. This combination reflects dysfunction in cerebellar and cortical pathways due to the depressant substance, and it can quickly progress to more serious problems like respiratory depression. That urgency is why this sign warrants prompt assessment of airway, breathing, and circulation and close monitoring for potential deterioration.

Nausea is nonspecific and can accompany many conditions, so it doesn’t specifically indicate CNS depressant toxicity. An increased heart rate with tremor suggests sympathetic activation or withdrawal rather than pure CNS depression. A person who is clear and alert is not showing signs of CNS depressant effect, so that reporting doesn’t fit toxicity.