First manic episode and bipolar I initiation (MEQ)

(i) Assessment priorities. Structure risk, medical exclusion, MSE, substance, collateral, capacity/legal. Risk: aggression/irritability, financial ruin, sexual disinhibition, driving, vulnerability, absconding, suicide (mixed features not yet prominent but screen). Medical exclusion: observations and glucose reassuring; still exclude encephalopathy, infection, endocrine, neurological red flags; baseline bloods and ECG before lithium/valproate/SGA. MSE with quoted grandiosity and pressure of speech. Cannabis timeline versus primary polarity. Collateral from mother including family lithium response. Capacity for treatment decisions; if incapacitous with high risk, consider involuntary pathway under local statute using least-restrictive principles — do not invent foreign section numbers.[4]

(ii) Working diagnosis and differentials. Working diagnosis: first manic episode / bipolar I disorder, current episode manic, with cannabis use contributing as precipitant or comorbidity. Differentials: substance/medication-induced manic symptoms (cannabis may contribute but grandiosity, sleeplessness and family history support primary bipolar spectrum); brief psychotic disorder if psychosis dominates without clear mood (not the lead here); schizophrenia spectrum less likely with acute polarity and family affective history; organic mania if atypical features emerge; ADHD does not produce new-onset week-long decreased sleep need and grandiosity in a previously well adult. Discriminators: attention/fluctuation, substance timeline, physical signs, collateral premorbid function.[4]

(iii) Acute management. Likely admission. Low-stimulation environment; restore sleep (short-term benzodiazepine e.g. lorazepam as needed). Start polarity-safe antimanic therapy after baselines. Example regimen: olanzapine 10–15 mg oral at night (titrate toward 10–20 mg) plus lithium initiated at 450–900 mg/day in divided or night dosing with plan to titrate to 12-hour trough roughly 0.8–1.2 mmol/L in acute mania, checking level at 5–7 days; or valproate loading where pregnancy is not an issue and protocol supports. Combination mood stabiliser + SGA is appropriate for severe mania. Monitor weight, glucose/lipids, sedation, EPS/akathisia, renal/thyroid/calcium for lithium. Avoid antidepressant. Document legal status and leave arrangements.[2][4]

(iv) Maintenance after remission. Continue effective acute regimen into early recovery, then simplify toward a long-term preventive agent. Lithium is first-line for many bipolar I patients when tolerated: BALANCE showed lithium monotherapy superior to valproate monotherapy for relapse prevention, with combination also effective.[1] Lithium also carries an anti-suicide evidence signal.[3] Duration after a single mania is commonly at least 6–12 months and often longer with high risk or incomplete recovery; shared decision-making with psychoeducation is essential.[4]

(v) Cannabis and early warning signs. Cannabis, especially frequent high-THC use, can precipitate and worsen mood episodes; cessation is high-yield. Early warning signs: falling sleep need, increased goal-directed activity, irritability, spending spikes, racing thoughts. Agree a written relapse plan with mother (with consent): who to call, when to escalate medication review, and crisis contacts.[4]