Tirzepatide-associated severe euvolemic hyponatremia with syndrome of inappropriate antidiuretic hormone secretion-compatible biochemical features.
Nithin Tumkur Prasad
✦ AI-curated · Sources linked
Case in brief
A woman with type 2 diabetes and morbid obesity, taking regular insulin and chronic torsemide, developed anorexia, weakness, and drowsiness 10 days after receiving tirzepatide. She was clinically euvolemic, with serum sodium of 104 mmol/L and calculated serum osmolality of 224 mOsm/kg. Renal, hepatic, hematologic, acid-base, and other endocrine parameters were normal; urinary sodium remained elevated after torsemide was stopped. The biochemical findings were compatible with SIADH. Fluid restriction and hypertonic saline were followed by progressive sodium correction and clinical improvement.
What made this case unusual
Severe symptomatic euvolemic hyponatremia with SIADH-compatible biochemical features occurred shortly after tirzepatide administration, in a patient also taking chronic torsemide.
Diagnostic / clinical pearl
In a patient taking tirzepatide who develops reduced intake or gastrointestinal symptoms, severe hyponatremia may present with euvolemia and SIADH-compatible findings; assess serum sodium and interpret urinary sodium in light of diuretic use.
Why it matters
The report raises a potential association between tirzepatide and severe hyponatremia, supporting consideration of electrolyte monitoring when patients on incretin-based therapy develop significant gastrointestinal symptoms or reduced oral intake.