Ketamine is a dissociative drug used in emergency medicine that also has become popular recreationally. Acute adverse effects include impaired consciousness, dizziness, irrational behavior, hallucinations, abdominal pain, and vomiting. Chronic use can impair verbal information processing and cause cystitis and cholangiopathy. Diagnosis of acute intoxication relies on patient history and clinical features such as vomiting, sialorrhea, or laryngospasm; chronic effects are confirmed by endoscopic retrograde cholangiopancreatography for cholangiopathy and cystoscopy for cystitis. Treatment of acute toxicity is supportive, with benzodiazepines recommended for agitation and excess neuromuscular activity. Chronic effects are typically reversible with abstinence.
A series of 10 patients who suffered adverse effects from the hallucinogen 25B-NBOMe showed hallucinations and violent agitation, along with serotonergic and stimulant signs such as dilated pupils, rapid heart rate, high blood pressure, and elevated body temperature. Most patients (7 out of 10) required sedation with benzodiazepines. Peak plasma levels of the drug ranged from 0.7 to 10.1 ng/ml. Management should be supportive, focusing on preventing self-harm, with high doses of benzodiazepines possibly needed to control agitation and active management for significant hyperthermia.