Primary polydipsia Alcoholism may cause physiological thirst since ethanol inhibits vasopressin, the hormone primarily responsible for water retention in osmoregulation. The following conditions should also be excluded: DI, cerebral salt wasting, pseudohyponatraemia caused by hyperlipidemia or hyperparaproteinemia, SIADH, mineralcorticoid deficiency, salt-wasting nephropathy, nephrotic syndrome, chronic heart failure and cirrhosis. Tobacco smoking is an often overlooked factor linked to hyponatremia, due to the ADH-releasing effect of nicotine, although this is usually limited to heavy smokers. One study suggested that around 70% of patients with self-induced polydipsia were tobacco smokers. Diagnostic tests for primary polydipsia usually involves the fluid deprivation test to exclude ADH
Primary polydipsia problems. The desmopressin test is also used, in which the synthetic hormone is used as a diagnostic workup to test for inappropriate secretion of vasopressin, as seen in DI and SIADH. Psychogenic polydipsia is found in patients with mental illnesses, most commonly schizophrenia, but also anxiety disorders and rarely affective disorders, anorexia nervosa and personality disorders. PPD occurs in between 6% and 20% of psychiatric inpatients. It may also be found in people with developmental disorders, such as those with autism. While psychogenic polydipsia is usually not seen outside the population of those with serious mental disorders, it may occasionally