In which patient population are vasopressin antagonists contraindicated due to the risk of nephrotoxicity?

Vasopressin antagonists, such as tolvaptan and conivaptan, are used primarily to treat conditions like hyponatremia and heart failure. However, in patients with end-stage renal disease (ESRD), the use of these agents is contraindicated due to the risk of nephrotoxicity and the impact on renal function.

In ESRD, the kidneys have significantly reduced function, and administering vasopressin antagonists can exacerbate this condition by further impairing renal function or causing an imbalance in electrolytes and fluid homeostasis. Since ESRD patients often depend on their remaining renal function, the potential for these medications to induce complications poses a high risk.

The contraindication in ESRD patients stems from the pharmacokinetics and pharmacodynamics of vasopressin antagonists, as these patients may not be able to metabolize and excrete the drug effectively, leading to potential accumulation and associated adverse effects on the kidneys. Thus, the specific risk associated with vasopressin antagonists in this population highlights the importance of careful consideration when managing patients with significant renal impairment.