The benefit of lithium carbonate adjunct in refractory depression--fact or fiction?

Our group attempted to validate previous claims of rapid success with lithium carbonate adjunct therapy in antidepressant-resistant depression. Seven depressed patients volunteered for a study of placebo controlled, double-blind design. During their treatment on general hospital psychiatric wards, these patients received antidepressant medication for a period of at least 21 days. While continuing to receive antidepressant medication after the 21 day period, four of the patients then received lithium carbonate, and three received placebo. This combination pharmacological therapy continued for a 48 hour period. After this time, six of the seven patients showed no significant improvement. The remaining patient, who had received lithium carbonate, improved markedly over the 48 hour period. However, this patient relapsed within one week. A review of the two most extensive studies claiming significant results with the lithium carbonate adjunct therapy was performed. We feel that they, as presented, leave serious doubt as to the validity of their conclusions. We conclude that on the basis of our work up to this point in time and the analysis of previous reports claiming otherwise, no valid evidence exists for a consistent therapeutic effect of lithium carbonate adjunct in antidepressant-resistant depression. It was also found that methodologic contamination necessitated the exclusion of an additional six patients from the double-blind trial. We conclude that in order to objectively examine the rapidly expanding field of biological psychiatry, teaching of clinical staff in basic research procedure should be stressed as a part of routine ward orientation.