Doctors who first noticed that the chemical element lithium caused mood stabilization were using it to treat gout. In 1949 an Australian psychiatrist, John Cade, was the first to publish a paper about using lithium to treat acute mania, but the FDA didn't approve the drug for use in bipolar disorder until 1970. Along the way it was found that lithium also has a positive effect on depression as well as mania and hypomania.
How does lithium work?
Researchers found in 1998 that lithium works by helping to keep the amount of a specific neurotransmitter, glutamate, at a consistent and healthy level between nerve cells in the brain. A neurotransmitter is a chemical that transmits nerve impulses from one neuron to the next.
This isn't to say that lithium's effect on glutamate is the entire answer. Scientists are still studying the mechanisms of lithium in bipolar disorder, and some intriguing genetic clues have been uncovered. A 2010 study demonstrated that lithium reduces brain inflammation.
There are still more questions than answers about how lithium works, but there's no doubt that for millions of people who have bipolar disorder, lithium makes a huge difference in their lives.