Tolvaptan in the Treatment of the Syndrome of Inappropriate Anti-Diuretic Hormone in Cancer Patients


OCAK B., ŞAHİN A. B. , DAKİKİ B., CANER B., ERTAŞ H., OYUCU ORHAN S., ...More

Eurasian Journal of Medical Investigation, vol.4, no.4, pp.490-494, 2020 (Peer-Reviewed Journal)

Abstract

Objectives: This study aimed to reveal the therapeutic efficacy and side effects of tolvaptan use in patients with hypotonic euvolemic hyponatremia caused by syndrome of inappropriate anti-diuretic hormone (SIADH) in our oncology clinic. Herein is presented the first real-life data on the use of tolvaptan in hyponatremia observed in cancer patients in Turkey to the researchers’ knowledge. Methods: Clinically euvolemic patients who had serum osmolality <275 mOsm/kg, urine osmolality >100 mOsm/kg, urine sodium concentration >40 mmol/L and were diagnosed with SIADH, were scanned via electronic data. In treatment, tolvaptan 15 mg/day was administered for 3 days. Results: Hypotonic euvolemic hyponatremia due to SIADH was diagnosed in 24 patients (16 males, 8 females) who followed up for malignancy. The median sodium value of the patients before tolvaptan treatment was 121.5 mEq/L. The median sodium concentrations in the 3 days of treatment were 126.0 mEq/L, 132.0 mEq/L and 137.0 mEq/L, respectively. In 6 patients, adverse effects were observed; none of them stopped or paused treatment, however. Only 2 patients were discharged, while the other patients died. Conclusion: The use of tolvaptan in the treatment of SIADH-induced hypotonic euvolemic hyponatremia provided an effective correction in serum sodium concentration, and improved the symptoms associated with hyponatremia.

Keywords: Cancer patients, hypotonic euvolemic hyponatremia, syndrome of inappropriate anti-diuretic hormone, tolvaptan