Lithium carbonate is one of the 590 medicines on the WHO Model List of Essential Medicines: those considered to satisfy the priority health needs of a population and that should be kept available at all times and at an affordable cost.
The prime use of lithium (as lithium carbonate or lithium citrate) is in the treatment of mood disorders, most commonly bipolar disorder but also schizophrenic disorders and major depressive disorder. Since the 1950s it has been the single most effective treatment for bipolar disorder, reducing the severity and frequency of episodes of mania, and is prescribed to millions of people worldwide. Despite this long and extensive use, its specific mechanism of action remains unknown.
The dosage has to be carefully monitored as lithium compounds are toxic in higher doses. The drink 7 Up originally contained lithium citrate and was marketed as ‘7 Up lithiated lemon soda’. Lithium was removed from the ingredients in 1948. The origins of the name 7 Up are not certain but according to one theory it is because the atomic mass of lithium is 7.