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 worsened outcomes.
- G) Schizophreniform disorder: Although rare, a new-onset psychotic disorder could present similarly. Failing to consider this diagnosis might delay appropriate treatment.
- Rare diagnoses
- A) Borderline personality disorder: This diagnosis does not directly explain the patient's acute symptoms and is not relevant to the immediate differential diagnosis.
- C) Generalized anxiety disorder: The patient's symptoms are not consistent with generalized anxiety disorder, which typically presents with excessive worry and anxiety.
- D) Intoxication, amphetamine: The patient's symptoms and history do not suggest amphetamine intoxication.
- O) Withdrawal, PCP: PCP withdrawal is less well-defined and less likely given the context of sedative overdose.