The origins of lithium therapy

Ores containing lithium were discovered in 1800. The new element was named in 1818 and lithium metal was first isolated in the same year. The first re corded medical use of lithium was in 1859 when it was used in the treatment of gout. The uric acid diathesis concept linked gout to a wide variety of other conditions, including mania and depression, and it was as a result of this that lithium was used to treat both of these latter conditions in the late 19th century. Although the uric acid diathesis concept persisted well into the 20th century, the use of lithium in medicine gradually died out, until in 1949 it was again successfully used in the treatment of manic exci tement. At about the same time, however, there were reports of toxicity ari sing from the uncontrolled ingestion of lithium salts used as taste substit utes for sodium chloride. Lithium therapy for mania was investigated only s poradically over the next few years until the appearance in 1954 of a repor t which not only confirmed the therapeutic efficacy of lithium against this condition, but also showed that adverse effects of lithium could be contro lled by monitoring serum lithium levels. In the early-to-mid 1960s, it was suggested that lithium not only acted acutely against mania, but could be u sed prophylactically to prevent recurrent depressive episodes. This finding was at first challenged on methodological and statistical grounds, the cla im for prophylactic efficacy being branded a 'therapeutic myth.' Subsequent work, however, demonstrated that the claims for prophylactic efficacy were well-founded and this led to the establishment of lithium treatment as a m ajor therapeutic modality in modern psychiatric practice. The use of lithiu m spread throughout the world, with particular interest being shown in the USA and UK where confirmatory studies were conducted. Whilst some claims we re made For an acute antidepressant effect of lithium, this appeared limite d to a subgroup of depressed patients; similarly, lithium was effective is schizophrenic patients only to the extent that it reduced associated manic excitement. A number of crises arose in the early years of lithium therapy, which seemed to pose a threat to the establishment of this treatment: thes e included reports of possible effects on the thyroid and kidney. However, later work showed that none of these effects was serious and that, properly managed, lithium therapy was both safe and effective. Lithium has now an e stablished place in psychiatric practice, although the introduction of newe r antidepressants has, to some extent, reduced the extent to which lithium is used. It remains the case, however, that lithium has properties not poss essed by the antidepressants, including the potential to reduce suicide rat es in at-risk populations, and the future may see a resurgence in the popul arity of this medication. The history of lithium therapy provides a fascina ting glimpse into the social and historical forces which have shaped modern medicine and the conceptual systems upon which present-day treatments are founded.