Lithium in pharmacology refers to use of the lithium ion, Li, as a drug. A number of chemical salts of lithium are used medically as a mood stabilizing drug, primarily in the treatment of bipolar disorder, where they have a role in the treatment of depression and particularly of mania, both acutely and in the long term. As a mood stabilizer, lithium is probably more effective in preventing mania than depression, and may reduce the risk of suicide. In depression alone (unipolar disorder) lithium can be used to augment other antidepressants. Lithium carbonate (Li2CO3), sold under several trade names, is the most commonly prescribed, while the citrate salt lithium citrate (Li3C6H5O7), the sulfate salt lithium sulfate (Li2SO4), aspartate and the orotate salt lithium orotate are alternatives.