Polydipsia: The forgotten thirst in psychiatry – a narrative review from India

ABSTRACT Polydipsia, defined as intake of over 3 liters of fluid/day, is frequently observed in psychiatric settings in association with illnesses such as schizophrenia, bipolar disorder, alcohol use disorder, and neurological conditions. It may lead to serious complications, including hyponatremia, seizures, and coma, and may complicate the course of psychiatric illnesses. Despite its clinical significance, studies on its prevalence, impact, and management in psychiatric patients are lacking. There is a paucity of recent data, particularly from India. This narrative review aims to synthesize Indian literature on polydipsia in psychiatric patients, summarizing its clinical characteristics, assessment, and management. We conducted a literature search on PubMed, Scopus, Web of Science, and Google Scholar (January 2000 to July 2025) using combinations of keywords: polydipsia, excessive fluid intake, psychiatric illness, mental disorder, and India. We found 18 case reports; no original studies or prior reviews were identified. Patient ages ranged from around 3 years to 74 years, with a male predominance (61%). Schizophrenia and obsessive-compulsive disorder were the most frequent psychiatric diagnoses (n = 3 each), followed by Mania (n = 2). Common features included increased thirst, polyurea, and hyponatremia; complications comprised seizures, urinary incontinence, agitation, and delirium. Diagnostic approaches included urine and serum osmolality, diurnal weight, and water deprivation test (WDT). Management involved fluid restriction, psychotherapy, and pharmacotherapy (second-generation antipsychotics, selective serotonin reuptake inhibitors, and Acetazolamide). Polydipsia in psychiatric patients in India is documented only through case reports, highlighting a critical evidence gap. There is a need for original Indian studies using robust methodologies.