A 58 year-old Polish lady was admitted to hospital after having had two tonic-clonic seizures. She reported a previous history of seizures but had been seizure-free for 10 years. In addition, she reported a 20 year history of hand spasms and perioral paraesthesia. As part of the investigation for seizures while she was living in Poland 10 years ago, CT head had shown bilateral basal ganglia calcification and on this basis she had been diagnosed with Fahrs disease. On admission, Chvosteks and Trousseaus signs were positive and ECG showed a prolonged QT interval. Blood tests were in keeping with primary hypoparathyroidism with an adjusted calcium of 1.18 mmol/L (2.20-2.60), phosphate of 2.19 mmol/L (0.80-1.50), undetectable PTH <0.7 pmol/L (1.6 -6.9) and 25-OH Vitamin D of 50 nmol/L (51-163). CT head showed extensive dense bilateral basal ganglia, thalamic, and cerebellar dentate nucleus calcification. A diagnosis of Fahrs syndrome associated with idiopathic hypoparathyroidism was subsequently made. Initial treatment was with intravenous calcium gluconate followed by oral sandocal and alfacalcidol. At 4-month follow-up, she denied any hand spasms or paraesthesia and had been seizure-free. There were no signs of neuromuscular excitability, and she reported feeling better than ever. Our case highlights the importance of excluding metabolic abnormalities in all patients with basal ganglia calcification and neuro-psychiatric presentation before diagnosing Fahrs disease. In this case, lack of investigation for metabolic abnormalities 10 years ago possibly resulted in a delayed diagnosis and treatment of idiopathic hypoparathyroidism. In addition, treatment of Fahrs syndrome is directed at correcting the specific metabolic abnormality, for example correction of hypocalcaemia, which reduces seizure frequency. In contrast, only symptomatic therapies such as anti-epileptics or anti-psychotics can be used in Fahrs disease. This therefore emphasises the importance of distinguishing between Fahrs disease and Fahrs syndrome as it affects both treatment and prognosis.