Psychiatric and Behavioral
What you must know
Depression: screen with PHQ-2 then PHQ-9. Treat moderate to severe disease with psychotherapy plus an SSRI; allow 4-6 weeks at therapeutic dose before declaring failure. Assess suicide risk directly and document plan, intent, means, and protective factors; ask about firearms. Bipolar disorder requires a mood stabilizer (lithium, valproate, or an atypical antipsychotic) - an antidepressant alone can trigger mania or rapid cycling. Anxiety disorders respond to CBT and SSRIs; benzodiazepines are short-term bridges only and are avoided in older adults because of falls, confusion, and dependence.
Substance use: screen with AUDIT-C or a single-question screen; manage alcohol withdrawal with benzodiazepines and thiamine, and know that naltrexone or acamprosate reduce relapse. Opioid use disorder is treated with buprenorphine or methadone. Schizophrenia is managed with antipsychotics plus metabolic monitoring (weight, glucose, lipids). ADHD treatment is stimulant or nonstimulant therapy with baseline cardiac assessment.
Eating disorders: anorexia nervosa has the highest mortality; watch for bradycardia, orthostasis, hypothermia, and hypophosphatemia during refeeding. Perinatal depression is common and SSRIs are appropriate. Distinguish delirium from dementia - acute, fluctuating inattention is delirium and demands a search for a medical cause.
Traps
- Starting an antidepressant in a patient with bipolar disorder.
- Reaching for a benzodiazepine in an older anxious patient.
- Attributing new psychiatric symptoms in an older adult to depression rather than delirium.
- Stopping an SSRI abruptly (discontinuation syndrome).
Rule of thumb
New behavioral symptoms in an older adult are delirium until a medical cause - infection, medication, withdrawal, metabolic - is excluded.