Seasonal and atypical depression — assessment and management (MEQ)

(i) Working diagnosis and differentials. Working diagnosis: recurrent major depressive disorder, seasonal pattern (winter-type), with atypical reverse vegetative features (hypersomnia, hyperphagia/weight gain). Justify seasonal pattern using multi-year regular onset and full spring remissions; confirm two seasonal episodes in two years without nonseasonal MDEs when history allows, and lifetime seasonal predominance. Map southern-hemisphere months correctly (winter mid-year in Melbourne). Differentials: bipolar depression with seasonal course; nonseasonal MDD with coincidental winter stress; hypothyroidism/OSA; delayed sleep-phase or shift-related circadian disorder; substance-related winter worsening; subsyndromal "winter blues" without full MDE (not her prior winters). Discriminators: mania/hypomania screen, thyroid/sleep history, substance timeline, functional severity and suicidality.[4]

(ii) Assessment priorities. Chart month-of-onset for at least two years; full MSE; expand passive death wishes into complete suicide risk assessment (intent, plan, means, protective factors); bipolar screen (elevated/irritable periods, reduced sleep need, grandiosity, risky behaviour, family history); medical screen and baseline labs as for MDD; ocular history and photosensitising drugs before high-intensity light; occupation/light exposure; pregnancy status if relevant; collateral if available; capacity and preference. SPAQ may support seasonality discussion but does not replace episode diagnosis.[4][5]

(iii) Acute winter management. Collaborative safety plan if ideation recurs. Psychoeducation that this is a treatable major depression pattern, not weakness. Bright light therapy: quality box ~10,000 lux, morning for ~20–30 minutes, eyes open toward device, daily through the symptomatic season; expect benefit often within 1–2 weeks if dose/timing adequate; counsel headache, eyestrain, insomnia, rare switch — her prior night use was incorrect timing. Offer antidepressant if preferred, severe, or light insufficient: e.g. fluoxetine 20 mg orally each morning (Can-SAD framing) or sertraline 50 mg orally daily, early review for activation/suicidality, titrate and allow 4–6 weeks at therapeutic dose. Measurement-based follow-up (PHQ-9). Escalate care if risk rises, psychosis, or non-response.[1][5][4]

(iv) Prevention. Because she is currently well with highly recurrent winters, plan anticipatory bupropion XL: start early autumn before expected onset (e.g. 150 mg orally once daily, increase to 300 mg once daily if tolerated/indicated), continue through winter high-risk months, taper in spring after risk window; counsel seizure risk factors, BP, insomnia/activation, and that this is prevention not a reason to ignore a breakthrough MDE. Alternative/adjunct: CBT-SAD skills for seasonal beliefs and behavioural activation with evidence for acute parity with light and possible multi-winter durability. Lifestyle: morning outdoor light, exercise, sleep schedule — adjunctive only.[2][3]

(v) Pitfalls. Treating as "just winter blues"; evening-only light; no bipolar screen; no suicide assessment because "seasonal"; inventing Mental Health Act sections; starting preventive bupropion only after she is already severely depressed mid-winter and calling it prevention; promising MAOIs as first-line without infrastructure; ignoring southern-hemisphere season mapping.[4]