Lithium pharmacology refers to use of the lithium ion, Li+, as a drug. A number of chemical salts of lithium are used medically as mood-stabilizing drugs, 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 certain bipolar patients. 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 lithium citrate (Li3C6H5O7) is also used in conventional pharmacological treatments. Lithium sulfate (Li2SO4) has been presented as an alternative[citation needed]. Lithium orotate is sometimes marketed as a "safe" natural alternative with fewer side effects than conventional lithium, yet caution must be taken with all of the active lithium salts.