Behavioral Health
Duration criteria decide the diagnosis
Most missed behavioral-health items are time-based. Schizophrenia needs continuous signs for at least 6 months with at least 1 month of active symptoms; schizophreniform disorder is the same picture for 1–6 months; brief psychotic disorder lasts under 1 month. Schizoaffective disorder requires delusions or hallucinations for 2 or more weeks in the absence of a mood episode. Major depressive disorder requires 2 weeks of at least 5 symptoms including depressed mood or anhedonia. A manic episode requires 1 week (any duration if hospitalization is required); hypomania requires 4 days. Bipolar I is defined by a single manic episode, not by depression severity. Acute stress disorder (3 days to 1 month) is the precursor to PTSD (over 1 month).
Withdrawal timelines are a classic trap
Alcohol and benzodiazepine withdrawal are the lethal ones. Alcohol tremor and hallucinosis appear at 12–48 hours, withdrawal seizures at 24–48 hours, and delirium tremens at 48–96 hours with autonomic instability. Opioid withdrawal is miserable but not fatal. Treat alcohol withdrawal with benzodiazepines and give thiamine before glucose to prevent Wernicke encephalopathy.
Capacity, consent, safety
Assess decision-making capacity through understanding, appreciation, reasoning, and communication of choice; competence is a legal determination. A patient with capacity may refuse treatment. Duty to warn or protect applies when a patient threatens an identifiable victim.
Rule of thumb
For any new psychiatric symptom, ask two questions first: is there a medical or substance cause, and does the timeline actually meet the threshold?