lithium (Li), chemical element of Group 1 (Ia) in the periodic table, the alkali metal group, lightest of the solid elements. The metal itself—which is soft, white, and lustrous—and several of its alloys and compounds are produced on an industrial scale. This article explores what lithium is and the conditions it can treat. It also describes lithium's side effects, risks, and potential interactions with other drugs. Learn what lithium is, why it matters, where it’s found, and how it’s used in batteries, EVs, energy storage, and the clean energy transition. Lithium is a mood-stabilizing prescription medicine used to treat acute manic and mixed episodes in bipolar I disorder and provides maintenance therapy from age 7, reducing manic episode frequency and severity. Learn about side effects, warnings, and administration. Lithium (from Ancient Greek: λίθος, líthos, 'stone') is a chemical element; it has symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid element due to its low atomic mass and large atomic radius. Learn about the side effects of lithium, from common to rare, for consumers and healthcare professionals. Lithium is used to treat mania that is part of bipolar disorder (manic-depressive illness). It is also used on a daily basis to reduce the frequency and severity of manic episodes. Lithium toxicity, which is also called lithium overdose or lithium poisoning , is the condition of having too much lithium in the blood. This condition also happens in persons who are taking lithium in which the lithium levels are affected by drug interactions in the body. Lithium is the most commonly used medicine to treat bipolar disorder (BD). It is considered a mood regulator, and the mechanisms underlying this effect still need to be elucidated. Some modulations are involved in neuroprotection, including neuronal. Find out how lithium treats mood disorders such as mania and bipolar disorder, and how to take it. NHS medicines information on lithium – what it's used for, side effects, dosage and who can take it.