“For a week or two before my period I become a different person — rage, despair, I scare myself — then it lifts”

PREMENSTRUAL DYSPHORIC DISORDER (PMDD) is the severe, functionally impairing end of premenstrual disorders: prominent affective symptoms (irritability/RAGE, low mood/DESPAIR, anxiety, mood swings, feeling out of control) ± physical symptoms occurring in the LUTEAL phase (the 1–2 weeks before menstruation), damaging relationships/work, and RESOLVING shortly after the period starts with a SYMPTOM-FREE follicular interval — the cyclical timing with a symptom-free window being the diagnostic key. Distinguish it from ordinary (milder, non-disabling) PMS and from an underlying MOOD DISORDER with premenstrual exacerbation, where symptoms PERSIST through the cycle (worse premenstrually) rather than fully resolving. Confirm with a PROSPECTIVE symptom DIARY over at least two cycles, since retrospective recall is unreliable and the diary both confirms PMDD and excludes a persistent mood disorder. Assess severity and functional impact, and explicitly screen RISK — PMDD causes genuine distress and carries a real suicide/self-harm risk in the luteal phase — while validating strongly that this is a recognised medical condition, NOT "just PMS"/"just hormones" or a character failing (the validation is itself therapeutic after dismissal). Offer evidence-based treatment per RCOG Green-top Guideline No. 48 (2016): lifestyle measures; an SSRI (effective in PMDD, given continuously OR only in the luteal phase; unlicensed for PMS in the UK, dose per BNF; screen for bipolar features first and review within 1 week if at increased suicide risk, NICE NG222); combined hormonal contraception/ovulation suppression (a new-generation combined pill, drospirenone-containing usually more effective, cyclical or continuous, after a UKMEC check); CBT; risk explored without risk labels and with a safety plan (NICE NG225); and referral to gynaecology/specialist for severe/refractory cases (GnRH analogues ± add-back, rarely surgery), tailored to her preferences and contraceptive needs. The hidden agenda is feeling she is "going mad" and previously dismissed; recognise, confirm, assess risk, validate, and treat with shared decision-making.