Psychogenic polydipsia

Commonly encountered in patients with psychiatric disorders.

Presents with water-seeking and excessive drinking, sometimes accompanied by hyponatremia and water intoxication.

Neuropsychiatric manifestations of hyponatremia include headache, nausea, cramping, hyporeflexia, dysarthric speech, lethargy, confusion, seizures, and delirium. Coma and even sudden death can ensue as sodium status worsens.

Complications of psychogenic polydipsia include incontinence and enuresis, bladder dilation and hydronephrosis, renal and congestive heart failure, and osteoporosis and associated pathologic fractures.

Diagnosis is one of exclusion. Other medical causes of polydipsia, polyuria, and/or hyponatremia need to be ruled out.

Management includes fluid restriction and behavioral and pharmacologic therapy. Serum sodium should be vigilantly and frequently monitored, with judicious use of hypertonic saline to treat symptomatic or severe hyponatremia.

Polydipsia is excessive or abnormal thirst, accompanied by intake of excessive quantities of water or fluid. Psychogenic polydipsia (PPD), or primary polydipsia, is characterized by excessive volitional water intake and is often seen in patients with severe mental illness and/or developmental disability. There may be no physical effects, but hyponatremia can occur.