SUBSTITUTION OF IMMEDIATE-RELEASE VALPROIC ACID FOR DIVALPROEX SODIUMFOR ADULT PSYCHIATRIC-INPATIENTS

In a prospective open-label study the substitution of immediate-releas e valproic acid for divalproex sodium was evaluated in the treatment o f 47 adult psychiatric inpatients who had been stabilized on divalproe x for at least one month. After two weeks, no significant change in Cl inical Global Impressions scale (CGI) scores or in seizure frequency o ccurred, and serum valproate concentrations decreased by 14.4 percent (p=.001). One patient was restarted on divalproex because of gastroint estinal complaints. Among the 19 patients remaining hospitalized at si x months, mean CGI scores did not significantly change. Costs were red uced 83 percent; annual savings per patient was approximately $905, Th ese preliminary results suggest that many chronic psychiatric inpatien ts stabilized on divalproex may be safely switched to valproic acid.