Summary

A 48-year-old Filipino man presented after several episodes of worsening limb paralysis that occurred after drinking cola beverages. In the emergency department he was found to be hypokalaemic, and although he exhibited no symptoms of thyrotoxicosis he was biochemically hyperthyroid. Thyroid stimulating hormone receptor antibody serology was positive indicating Graves’ disease as the underlying cause of his hyperthyroidism. Intravenous potassium supplementation resulted in complete resolution of symptoms, and a diagnosis of thyrotoxic periodic paralysis was made. He was started on a regimen of propylthiouracil and propranolol and subsequently given radioiodine as the definitive treatment for Graves’ disease. There were no recurrent attacks of paralysis once a stable euthyroid state was achieved, and the patient was able to resume cola consumption without issue.