The unmasking of hidden severe hyponatremia after long-term combination therapy in exacerbated bipolar patients: a case series

We presented three clinical cases of patients affected by a long-term psychiatric disorder and under polypharmacotherapy for several months. After excluding other potential factors, we hypothesized that pharmacological treatment with a mood stabilizer (oxcarbazepine) associated with a benzodiazepine (delorazepam), a second-generation antipsychotic (olanzapine) or an antidepressant (fluvoxamine), triggered severe hyponatremia ([Na+] ≤125 mEq/L), serum hypo-osmolarity, and elevated inappropriate urine osmolarity added to more diluted sodium concentration. When we discontinued the treatment, clinical conditions of our patients improved, despite the previous administration of hypertonic saline jointly with water restriction. Psychiatrists should consider that bipolar patients on long-term polypharmacotherapy may present a higher risk of severe hyponatremia not clinically detectable. Consequently, routine laboratory tests should be periodically repeated as they represent the only available tool to unmask such electrolyte imbalances.
Source: International Clinical Psychopharmacology - Category: Psychiatry Tags: Case Report Source Type: research