Self-induced water intoxication in schizophrenic patients

This case report concerns two schizophrenic patients with "psychogenic" polydipsia, without any underlying somatic disease. Although case A showed a correlation between excessive water intake and severity of psychomotor disturbance, this could not be safely diagnosed as a water intoxication because the sodium serum level was normal. The lowered sodium serum level in case B, however, allowed us to conclude that the manifestation of grand mal was a sign of a genuine water intoxication. 27 casuistic studies on 67 patients with the syndrome of self-induced water intoxication in schizophrenics are then reviewed. Finally, a variety of diagnostic and pathogenetic problems of this syndrome is discussed, with special reference to the role of inadequate ADH secretion.