A 19-year-old man with agitation and nystagmus after possible drug use likely has intoxication with which substance?

• A. Alcohol intoxication
• B. Cocaine intoxication
• C. Cannabis intoxication
• D. PCP intoxication

Answer: (B)

When a young person presents with agitation after possible drug use, think about substances that provoke strong central nervous system arousal and autonomic activation. Cocaine does this by blocking reuptake of norepinephrine, dopamine, and serotonin, leading to a surge of sympathetic activity. That drives agitation, tachycardia, hypertension, diaphoresis, and hyperactivity. Nystagmus can occur with stimulant effects and high-dose cocaine use, especially in acute intoxication or poly-drug scenarios, so agitation with nystagmus fits cocaine intoxication.

Alcohol intoxication would more likely show slurred speech, ataxia, and disinhibition; cannabis tends to cause euphoria, slowed movements, conjunctival injection, and perceptual changes without prominent nystagmus; PCP intoxication is classically linked to marked nystagmus (often vertical) plus severe agitation or violent behavior and analgesia. So among these options, cocaine intoxication best aligns with agitation plus nystagmus in this vignette.