A 50-year-old woman presented with a two-day history of diarrhea, vomiting, progressive numbness around her mouth and generalized body cramps. One year before presentation, she had undergone a total thyroidectomy for a multinodular goiter. She also had a history of depression, hypertension and chronic renal impairment. She reported taking citalopram, rabeprazole for gastroesophageal reflux disease, calcium carbonate, levothyroxine and vitamin B12. Her vital signs were stable. Trousseau sign was evidenced a few seconds after the sphygmomanometer cuff was inflated to more than the systolic blood pressure on the left upper arm.