Re-response to tolvaptan after furosemide dose reduction in a patient with refractory ascites.

Tolvaptan is a new drug used for treating ascites induced by liver cirrhosis, and it is covered by health insurance in Japan. In the present report, we describe the case of a 74-year-old man with type C liver cirrhosis and refractory ascites. He was receiving furosemide and spironolactone daily, but still required repeat puncture for ascites removal. Administration of tolvaptan (3.75 mg/day) was started in addition to his existing medications, and was subsequently increased to 7.5 mg/day. However, after 2 months, the ascites again exacerbated. Nevertheless, after we discontinued the administration of furosemide, the tolvaptan became effective. This may be because furosemide administration decreases urine osmolality, resulting in a non-response to tolvaptan.