The influence of calcium in mental disorders has been considered over time. For example, intravenous calcium gluconate was used for treatment of periodic psychosis as late as the 1970s. Also, mental symptoms may be prominent in patients with hypercalcemia of various causes. The role of serum calcium in the switch process of manic-depressive disorder was studied in the late 1970s. Increases in serum calcium and phosphorus induced by treatment of bipolar-1 depressed patients with dihydrotachysterol-increased symptoms of hypomania. On the other hand, treatment with salmon calcitonin, which has the opposite effect, mitigated mania. Abrupt changes in serum calcium were implicated in the rapid changes in periodic psychosis [1]. A rationale for the employment of calcium channel blocking drugs was proposed after the observation that antipsychotic drugs of the diphenylbutylpiperidine type (pimozide, penfluridol, fluspiriline) were also potent inhibitors of calcium channels of the nitrendipine type. This pharmacological action, beyond the classical one of blocking D2 dopamine receptors, was implicated in the beneficial effects of these drugs on negative symptoms of schizophrenia [2].