Abstract
Indomethacin is a medication for nephrogenic diabetes insipidus. We herein report a case that was successfully treated with high-dose indomethacin (225 mg/day) for nephrogenic diabetes insipidus. A 35-year-old female had been receiving treatment for manic depression psychosis with lithium since 18 years of age. She was transferred to our emergency center due to an overdose of ingested phenobarbital and chlorpromazine. On the second hospital day, she developed hypernatremia and polyuria (over 450 ml/hr) which proved to be resistant to treatment with vasopressin. We diagnosed her to have nephrogenic diabetes insipidus. Because she had been taking lithium for manic depression psychosis for the previous 17 years, lithium was thus suspected to be the cause of diabetes insipidus. After diagnosing the patient to have nephrogenic diabetes insipidus, we discontinued lithium administration and switched the treatment to an indomethacin suppository (150 mg/day). However, her symptoms persisted. We considered that the blood concentrations of indomethacin were low, because the high creatinine clearance had been caused by the patient's polyuria. Therefore, we gradually increased the dose of indomethacin. Subsequently, high-dose indomethacin (225 mg/day) effectively brouight about an improvement in the symptoms of polyuria and hypernatremia. Our findings suggest that high-dose indomethacin therapy is an effective approach for treating patients with nephrogenic diabetes insipidus.
