Bipolar II vs unipolar, hypomania thresholds, lamotrigine and antidepressant risk — structured clinical viva

Nosology. Working diagnosis: bipolar II disorder with current hypomania (likely antidepressant-associated activation on sertraline monotherapy) and prior major depressions. Criteria: ≥4-day elevated pole with decreased sleep need and risk behaviour, no psychosis/hospitalisation described. If impairment becomes marked or psychosis appears, reclassify as mania/bipolar I.[4]

Assessment. Full polarity chart, suicide/violence/financial-sexual risk, substance screen, MSE, baselines before lithium/SGA, collateral, capacity. Compare with borderline PD using tempo (days vs hours), sleep need, and interpersonal triggers.[4]

Acute management. Safety and sleep restoration. Stop or taper sertraline under cover. Start polarity-safe agent, e.g. quetiapine toward 300 mg oral night (bipolar depression evidence includes BP-II samples) and/or lithium with trough monitoring; short-term benzodiazepine for sleep if needed.[2][4]

Antidepressant evidence. STEP-BD: adjunctive antidepressants did not improve durable recovery versus mood stabiliser plus placebo; monotherapy is harder to defend. Transition-to-mania data support activation vigilance.[1][5]

Lamotrigine. Use primarily for depression prevention with slow titration after acute pole settles; multi-trial acute monotherapy results largely disappointing — not a same-week rescue. Restart low after gap more than about 5 days; counsel rash/SJS stop rules.[3][4]

Prognosis counselling. BP-II is depression-predominant and not mild; early correct treatment, sleep regularity, and avoiding AD monotherapy improve course.[4]