Safety First: Risk & Rule-Outs
What must be checked before anything else
Before any elegant differential: is this person safe, is this actually medical, is this a substance, and is this mania? Four gates, every intake.
Gate 1: suicide and self-harm
Use a real tool, not a vibe: the Columbia Suicide Severity Rating Scale (C-SSRS) screener (ideation types 4-5, intent or intent-with-plan, or any recent behavior drives the high-risk pathway) or the 4-item the Ask Suicide-Screening Questions tool (ASQ).
A positive screen leads to a brief assessment, a Stanley-Brown safety plan, and lethal-means counseling. 988 goes on every plan. No-suicide contracts are out; safety planning is the standard.
The Diagnostic and Statistical Manual of Mental Disorders, fifth edition, text revision (DSM-5-TR) added codes for suicidal behavior and nonsuicidal self-injury so risk can live visibly in the record.
Gate 2: medical mimics
Thyroid disease impersonates depression and anxiety, sleep apnea impersonates depression and ADHD, anemia and B12 deficiency impersonate fatigue-depression, and delirium impersonates everything acutely. New client, no medical workup in the last year, plus new psychiatric symptoms: ask about the last physical and coordinate with their primary care provider (PCP) before locking a formulation.
Gate 3: substances and medications
Ask, every intake, without exception: alcohol, cannabis, stimulants, prescriptions (including someone else's), caffeine dosage, and nicotine. Substance-induced mood, anxiety, and psychotic presentations are common, and steroids, stimulants, and even high-dose caffeine mimic primary disorders.
Gate 4: mania screening before any depression referral
Every depressed client gets screened for lifetime mania or hypomania before an antidepressant referral, because an antidepressant alone can destabilize bipolar disorder. Ask about distinct periods of decreased need for sleep with unusual energy, spending, or plans. The Mood Disorder Questionnaire (MDQ) helps but a 2024 meta-analysis puts its sensitivity near 0.62: it misses a third of true bipolar cases, so history beats the checkbox.
Alcohol and benzodiazepine withdrawal can kill (seizures, delirium tremens); opioid withdrawal usually cannot but overdose after tolerance loss does. Command hallucinations, first-episode psychosis, and acute mania are same-week psychiatric referrals, not next-month.