The prophylactic efficacy of lithium - transient or persistent?

It has been reported recently that the prophylactic efficacy of lithium is a transient phenomenon in many patients. Other studies suggest sustained ef ficacy against affective recurrences for many years. As this issue is of ma jor therapeutic relevance, published literature considering changes in lith ium efficacy over time has been reviewed. The present review includes a cri tical evaluation of the data and the methodology which yielded these contro versial results. Considering the published data discussed in this review, t he balance of evidence does not indicate a general loss of lithium efficacy in the prophylaxis of major affective disorders. A supposed persistence of the prophylactic effects in general does not, however, exclude the reappea rance of affective recurrences after years of successful treatment in indiv idual cases. Possible reasons for this phenomenon are discussed.