Serum calcium and magnesium levels in chronic schizophrenics.

Serum calcium and magnesium levels were studied during neuroleptic treatment in a group of 29 chronic schizophrenic inpatients who had previously remained drug free for at least 4 weeks. The drug-free values of both electrolytes were not significantly different between patients and controls. In three patients who developed catatonic stupor during the drug-free period, calcium was significantly increased at the onset of the catatonic manifestations. Both electrolytes were significantly decreased in the whole group during treatment; the magnitude of the decrease was independent of the neuroleptic used. No correlation was found between the observed increase in prolactin and calcium changes. Patients who remained free of extra-pyramidal symptoms had a higher mean drug-free magnesium to calcium ratio compared to those who developed such symptoms. Our study provides evidence for an interconnection between serum electrolyte changes and neuroleptic drug action.