A 20-year-old college student is brought to the emergency department by his roommate. The patient is frightened and claims that campus police are following him and plotting to kill him. His roommate says that the patient seemed "totally normal" until a few days ago, when he began to stay up all night to prepare for final exams. The patient has no known medical or psychiatric history, but his father has schizophrenia. Blood pressure is 150/95 mm Hg and pulse is 110/min. Examination shows clear lungs and tachycardia with normal S1 and S2. The abdomen is soft and nontender. Extraocular movements are intact, and the pupils are dilated. The patient is diaphoretic. He appears hypervigilant, paces during the examination, and has mildly pressured speech. Which of the following is the most likely diagnosis in this patient?
The misuse of stimulants by college students to enhance academic performance is prevalent. This patient's acute onset of paranoia, restlessness, and hypervigilance, and physical signs of mydriasis, tachycardia, hypertension, and diaphoresis, are most likely due to stimulant intoxication. Transient paranoid psychosis can develop in intoxication with all major stimulants, including prescription medications for attention-deficit hyperactivity disorder (eg, amphetamines, methylphenidate). Substance-induced psychotic disorder is diagnosed when stimulant intoxication presents with prominent psychotic symptoms.
Substance-induced psychotic disorders must be differentiated from primary psychiatric disorders such as bipolar manic episodes and psychotic disorders. This student's prominent physical signs and lack of psychiatric history, combined with the temporal association between staying up to study and acute onset of psychosis, make a stimulant-induced psychotic disorder more likely.
(Choice A) Patients experiencing a bipolar manic episode can also have decreased sleep, pressured speech, physical restlessness, and psychotic features. However, the temporal association of studying for exams and the patient's abnormal vital signs, mydriasis, and diaphoresis make substance intoxication more likely.
(Choice B) Primary psychotic disorders are diagnoses of exclusion that require ruling out substance use and medical etiologies. Brief psychotic disorder is a rare condition characterized by acute onset of ≥1 psychotic symptoms (eg, delusions, hallucinations, disorganized speech or behavior) lasting ≥1 days but <1 month, with eventual complete resolution. This patient's physical findings (ie, mydriasis, tachycardia, hypertension, diaphoresis), the prevalence of stimulant misuse on college campuses, and the temporal association between intense studying and symptom onset make substance-induced psychosis much more likely than brief psychotic disorder.
(Choices C and D) These diagnoses would not be considered at this point due to insufficient duration of psychotic symptoms. The essential feature of delusional disorder is ≥1 delusions lasting ≥1 months without other psychotic symptoms. Schizophreniform disorder involves ≥2 psychotic symptoms lasting ≥1 months but <6 months.
Educational objective:
Stimulant intoxication can present with paranoid ideation and must be differentiated from primary psychiatric disorders. Physical signs of stimulant intoxication include mydriasis, tachycardia, hypertension, and diaphoresis.