Graves’ disease, the leading cause of hyperthyroidism, often overlaps with menopausal transition in women over 50. This coexistence intensifies vasomotor symptoms such as hot flashes and excessive sweating while promoting cardiovascular instability, including hypertension and altered nocturnal blood pressure patterns. Thyroid dysfunction elevates systolic blood pressure and vascular stiffness, while menopause exacerbates risks through estrogen decline and autonomic changes. This case highlights diagnostic and therapeutic challenges in managing these overlapping conditions in primary care.A 52-year-old postmenopausal woman presented with a history of Graves’ disease treated with thiamazole, accompanied by persistent hot flashes and profuse sweating. She reported recent home blood pressure (BP) spikes—afternoon readings around 150/95 mmHg and morning values near 140/90 mmHg—despite normal clinic measurements (<140/90 mmHg) and heart rates ≤80 bpm without palpitations. Echocardiography showed left atrial wall thickening and ventricular hypertrophy, indicating early left ventricular hypertrophy likely from long-standing undiagnosed hypertension. Thyroid tests confirmed ongoing Graves’ activity. Prior attempts to stop thiamazole caused TSH suppression and worsened BP fluctuations. Ambulatory monitoring confirmed episodic spikes.This case is noteworthy for illustrating the complex interplay between active Graves’ disease, persistent postmenopausal vasomotor symptoms, and masked/white-coat-normal hypertension with home spikes and early echocardiographic evidence of target-organ damage (LVH), where standard attempts to withdraw antithyroid therapy provoked BP instability.This case distinctively features masked hypertension with preserved heart rate in a postmenopausal patient with active Graves’ disease. Antithyroid drug withdrawal triggered rebound hyperthyroidism and BP instability despite lacking typical sympathetic symptoms. Early echocardiographic evidence of target-organ damage emphasises the subtle cardiovascular consequences of combined endocrine and menopausal influences.The case illustrates that antithyroid monotherapy may inadequately address cardiovascular effects when hyperthyroidism coincides with menopause. Evening angiotensin receptor blocker administration provides consistent 24-hour control, complementing thyroid management and mitigating risks in this population.Starting telmisartan 40 mg nightly with low-dose thiamazole 5 mg daily rapidly normalised BP, resolved spikes within weeks. This dual-therapy model offers a safe, practical framework for similar complex presentations in family medicine.