Lithobid controlled-release and extended-release tablets are used for treating manic episodes in patients with bipolar disorder. It is also used to reduce the frequency and decrease the severity of manic episodes in patients with bipolar disorder. It may also be used for other conditions as determined by your doctor. Lithobid controlled-release and extended-release tablets are an antimanic agent. Exactly how Lithobid controlled-release and extended-release tablets works is unknown, but it may work by altering the balance of certain chemicals in the brain.