• A multi-institutional cooperative study comparing lithium carbonate with chlorpromazine was conducted, using a controlled double-blind design in a series of 80 cases of endogenous manic psychosis, to evaluate the drugs' clinical utility and efficacy, characteristics of therapeutic effect, and side-effects. Dosages employed were consistently at an equipotent ratio of 4:1 (lithium carbonate:chlorpromazine).
Physicians' overall ratings showed lithium carbonate as significantly superior to chlorpromazine in efficacy for manic psychosis. Improvements of basic mood and of disturbance in speech and voice were prominent with lithium carbonate. Onset of the therapeutic effect of lithium carbonate was within ten days of medication in 65% of the patients, significantly faster than with chlorpromazine. Side-effects encountered with lithium carbonate therapy at dose levels not higher than 1,800 mg/day were milder and less frequent compared with those seen with chlorpromazine.