Differential Diagnosis
- Single most likely diagnosis
- H) Withdrawal, barbiturate: The patient's symptoms, including visual hallucinations, disorientation, coarse tremors, and inability to perform fine motor tasks (writing his name), began 20 hours after a sedative overdose. These symptoms are consistent with barbiturate withdrawal, which typically starts 12-24 hours after the last dose.
- Other Likely diagnoses
- B) Brief psychotic disorder: The patient's visual hallucinations and disorientation could suggest a brief psychotic disorder, but the presence of coarse tremors and the temporal relationship to sedative ingestion make this less likely.
- E) Intoxication, barbiturate: Although the patient overdosed on sedatives, the timing of his symptoms (20 hours later) suggests withdrawal rather than ongoing intoxication.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- F) Intoxication, PCP: While PCP intoxication can cause hallucinations and altered mental status, it is less likely given the context of sedative overdose. However, missing PCP intoxication could lead to inappropriate treatment and worsen the patient's condition.
- G) Schizophreniform disorder: Although rare, a schizophreniform disorder could present with similar symptoms. Failing to consider this diagnosis might lead to delayed treatment of a potentially severe psychiatric condition.
- Rare diagnoses
- A) Borderline personality disorder: This diagnosis is unlikely to explain the patient's acute symptoms, which are more suggestive of a substance-related or withdrawal syndrome.
- C) Generalized anxiety disorder: The patient's symptoms are too severe and include hallucinations, making generalized anxiety disorder an unlikely diagnosis.
- D) Intoxication, amphetamine: The context of sedative overdose and the patient's symptoms do not suggest amphetamine intoxication.
- O) Withdrawal, PCP: PCP withdrawal is less well-characterized and less likely to cause the patient's symptoms compared to barbiturate withdrawal.