Introduction: Wilson disease, an inherited autosomal recessive disorder of copper metabolism, is characterized by pathological copper accumulation. The disease is potentially treatable and usually caused by mutations in the ATP7B gene, encoding the transmembrane copper-transporting adenosine triphosphatase. Despite its well-documented neurological and hepatic manifestations, electrolytes disturbances, including hypermagnesemia, remained under-reported and rarely associated with the disease.  Case Presentation: A married Asian, Pakistani Punjabi, male from a middle-class family in his late 20s was admitted to the neurology ward of a tertiary care hospital with no previous medical history of disease. Initial assessments illustrated vital signs: body temperature 98°F, blood pressure 120/70 mmHg, random blood glucose level 81 mg/dl, pulse 82 beats per minute, oxygen saturation 98%, and hydration status (input: 1500 ml, output: 1000 ml). Physical examination revealed pallor on face and normal eyes, but mild silvery-brown edges in the corneas of both eyes (Kayser-Fleischer rings). Screening with mini nutrition assessment - short form, indicated malnourishment with a score of 4 (score: 0–7 signifies malnourished), accompanied by a body mass index of 20.43 kg/m². The subjective global assessment form showed a 10.93% weight loss within one month. Hypermagnesemia was prominent, with serum magnesium levels exceeding 2.2 mg/dl. Liver function tests revealed elevated aspartate transaminase levels. Conclusion: Wilson’s disease patients could develop severe malnutrition after the onset of the disease, hypermagnesemia, a dry white tongue, mouth sores despite good oral hygiene, and fatigue due to low oxygen supply, as indicated by low levels of haemoglobin in the blood.