Clinical Scenario:
A 14-year-old boy is brought to the emergency department because of sudden confusion and abnormal behavior. He is anxious, intermittently laughing, and reports that the surroundings feel unreal. His pulse is 118/min and blood pressure is 132/78 mmHg. Pupils are mildly dilated. He is afebrile, has normal oxygen saturation, and there are no focal neurological findings. His friends report that he had been using a new “high-potency” cannabis product shortly before symptoms began.
Which of the following is the most appropriate initial management?
A. Activated charcoal
B. Benzodiazepine
C. Flumazenil
D. Naloxone
E. Sodium bicarbonate
Correct answer & Explanation:
Correct Answer: B. Benzodiazepine
Explanation: Cannabis Intoxication
This adolescent has acute cannabis intoxication, most likely related to the use of a high-potency cannabis product. Cannabis intoxication can produce a combination of tachycardia, anxiety, impaired attention, altered perception, euphoria, paranoia, hallucinations, and depersonalization or derealization. High-potency products can produce more pronounced neuropsychiatric symptoms, particularly in inexperienced users.
The key features in this case are:
- Recent cannabis exposure
- Anxiety and abnormal behavior
- Intermittent inappropriate laughter/euphoria
- A feeling that the surroundings are unreal (derealization)
- Mildly dilated pupils
- Tachycardia
- No fever, hypoxia, focal neurological deficit, or evidence of a primary neurological emergency
Why is benzodiazepine the best answer?
There is no specific antidote for acute cannabis intoxication. Initial management is primarily supportive, including a quiet environment, reassurance, reduction of external stimulation, monitoring of vital signs, and assessment for co-ingestants or other causes of altered mental status.
When cannabis intoxication produces significant anxiety, panic, agitation, or severe psychological distress, a benzodiazepine can be used for symptomatic treatment. Agents such as lorazepam or midazolam may reduce anxiety and agitation.
Therefore, among the options given, benzodiazepine is the most appropriate pharmacological intervention.
If the patient develops severe persistent psychotic symptoms, an antipsychotic may be considered. However, that is not the presentation described here, and an antipsychotic is not one of the available options.
Why the other options are incorrect
A. Activated charcoal — Incorrect
Activated charcoal is not routinely indicated for acute cannabis intoxication, particularly when the exposure is from inhalation or when the patient is already symptomatic. Gastrointestinal decontamination is generally not useful for the typical presentation of cannabis intoxication and may introduce aspiration risk in a patient with altered mental status.
C. Flumazenil — Incorrect
Flumazenil is a benzodiazepine receptor antagonist and is used selectively for significant benzodiazepine toxicity. There is no evidence in this case of benzodiazepine poisoning. In addition, flumazenil can precipitate seizures in patients with benzodiazepine dependence or mixed drug overdose and is therefore not a routine antidote for undifferentiated intoxication.
D. Naloxone — Incorrect
Naloxone is an opioid antagonist. It is indicated when opioid toxicity is suspected, particularly when there is respiratory depression, depressed consciousness, and/or miosis. This patient instead has tachycardia, mild mydriasis, anxiety, and perceptual changes following cannabis exposure.
E. Sodium bicarbonate — Incorrect
Intravenous sodium bicarbonate is used in selected poisonings causing sodium-channel blockade, particularly tricyclic antidepressant toxicity with QRS widening or ventricular dysrhythmias. It has no role in routine management of uncomplicated cannabis intoxication.
Exam Pearl
Acute cannabis intoxication = supportive care first.
If significant anxiety, panic, or agitation is present, a benzodiazepine may be used for symptomatic relief.
Think:
Cannabis → tachycardia + anxiety + altered perception/derealization ± paranoia/hallucinations
There is no specific cannabinoid antidote.
Important pediatric point
Because this is a 14-year-old, the emergency assessment should not stop after identifying cannabis exposure. The clinician should assess for co-ingestion, trauma, hypoglycemia, infection, neurological disease, and other causes of altered mental status when clinically indicated. Once medically stabilized, the adolescent should receive an appropriate psychosocial and substance-use assessment.
You can also practice another MCQ on Acetaminophen poisoning.
References
- Sarkar S, Bhatia G, Dhawan A. Clinical practice guidelines for assessment and management of patients with substance intoxication presenting to the emergency department. Indian J Psychiatry. 2023;65(2):196-211. doi:10.4103/indianjpsychiatry.indianjpsychiatry_490_22.
- Cannabis-associated emergencies in the emergency department. Dtsch Arztebl Int. 2025.
- Clinical Practice Guidelines on Assessment and Management of Substance Abuse Disorder in Children and Adolescents. Indian J Psychiatry. 2019;61(Suppl 2):S333-S342
