Abstract
JS, a 42-year-old artificial inseminator in a veterinary hospital, reported with frequent dryness of mouth and throat, fearfulness, anxious foreboding, excessive thirst, increased quantity of water drinking (approximately 7 L day−1) and passing excess urine. The symptoms started 5 months earlier with insidious onset and progressive course. The patient needed admission as it was extremely distressing and was affecting his occupational and social functioning. Initial observation did not reveal any water intoxication.
A thorough investigation ruled out an organic basis for the symptoms. The patient was subjected to a water deprivation test for 12–18 hours, where an increased urine osmolarity to values greater than plasma osmolarity [1] were recorded. The patient was diagnosed to be suffering from primary polydipsia.
A detailed evaluation revealed his conflict with higher officials at his workplace over the previous 6 months. Initially, he developed an abrupt onset of a choking sensation and dryness of the mouth. He subsequently started substituting a compulsive water-drinking behaviour for his excessive thirst. The patient was subjected to a strict fluid restriction regimen. Symptoms of polydipsia regressed. As examination of his mental status revealed features of distress and anxiety, he was started on selective serotonin re-uptake inhibitor and low-dose benzodiazepine along with supportive psychotherapy. Periodic evaluation revealed a good improvement. The patient was discharged after 2 months and resumed his job.
Psychogenic polydipsia is an unusual clinical disorder characterized by excessive water drinking in the absence of a physiological stimulus to drink [2]. Resultant water intoxication can lead to deleterious effects such as hyponatremic encephalopathy, seizure, coma and even death [3], [4].
Most epidemiological surveys performed in long-term psychiatric hospitals have shown that psychogenic polydipsia occurs frequently among chronic psychiatric patients, particularly those with schizophrenia. Other psychiatric diagnoses have also been associated with polydipsia, including affective disorders, mental retardation and personality disorders [3], [4].
In our case, psychogenic polydipsia was followed by acute stress. It is possible that there is not one single type of psychogenic polydipsia but several subtypes, the aetiology being multifactorial [5].