Case files of the medical toxicology fellowship of the California poison control system-San Francisco: calcium plus digoxin-more taboo than toxic?

A 68 year old woman with a history of diabetes mellitus presented to the emergency department after experiencing several days of nausea and vomiting. Recorded vital signs included: blood pressure 98/32 mm Hg, heart rate 69 bpm, "normal" respirations, and no fever. Her initial ECG revealed peaked T waves and regular rhythm with no visible P waves. Initial serum electrolytes were notable for a potassium level of 7.7 mmol/L, and a creatinine level of 9.6 mg/dL (849 micromol/L). She was unable to provide a list of her current medications or other medical history. There was no old chart immediately available for comparison.