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Difficulty: MediumSubstance-Related and Addictive Disorders

Match each distinct clinical presentation to its most likely substance-related diagnosis.

  • Piloerection, excessive yawning, rhinorrhea, and mydriasis in a highly restless patient.Opioid withdrawal syndrome
  • Rotary nystagmus, apparent analgesia, and sudden aggressive outbursts in a trauma bay setting.Phencyclidine (PCP) intoxication
  • Conjunctival injection, significant dry mouth, and tachycardia in a lethargic adolescent.Cannabis intoxication
  • Profound disorientation, visual hallucinations, and autonomic instability peaking three days post-admission.Alcohol withdrawal delirium

Answer

Piloerection and yawning map to opioid withdrawal; rotary nystagmus maps to PCP intoxication; conjunctival injection maps to cannabis intoxication; and delayed autonomic instability with hallucinations maps to alcohol withdrawal delirium.
Each clinical presentation contains hallmark signs of specific substance states. Opioid withdrawal is uniquely characterized by yawning, piloerection (goosebumps), rhinorrhea, and mydriasis. Phencyclidine (PCP) intoxication is identifiable by rotary or vertical nystagmus combined with violent behavior and apparent decreased pain perception. Cannabis intoxication typically presents with conjunctival injection (red eyes), dry mouth, and tachycardia. Finally, alcohol withdrawal delirium (delirium tremens) is a medical emergency that typically peaks 48 to 96 hours after the last drink, presenting with altered sensorium, visual hallucinations, and severe autonomic instability.

Step-by-Step Solution

1
Analyze the first presentation featuring piloerection and yawning.
These are classic signs of sympathetic hyperactivity associated specifically with opioid receptor uncoupling and withdrawal.
Identifying the specific toxidrome differentiates opioid withdrawal from other withdrawal syndromes.
2
Analyze the second presentation featuring rotary nystagmus and aggression.
The presence of rotary or vertical nystagmus strongly points to NMDA receptor antagonism caused by phencyclidine.
Nystagmus combined with violent behavior is the pathognomonic sign of PCP over other stimulants.
3
Analyze the third presentation featuring conjunctival injection and dry mouth.
These are mild sympathomimetic and anticholinergic-like effects typical of cannabinoid receptor activation.
Recognizing conjunctival injection helps isolate this specific widely-used substance from pure depressants.
4
Analyze the fourth presentation featuring delayed hallucinations and autonomic instability.
A 72-hour timeline post-admission with severe sympathetic overdrive indicates a life-threatening late-stage withdrawal state.
Timing is critical to differentiate early withdrawal phenomena from late-stage delirium tremens.

Key Concept

Substance-Related Toxidromes and Withdrawal Syndromes
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Topics

Substance-Related and Addictive Disorders

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