Imipramine, released in the 1950s by Ciba-Geigy, was the first tricyclic antidepressant on the market. Imipramine was originally developed to treat psychotic disorders such as schizophrenia, but was not effective. It did show effectiveness in the treatment of depression, including major depression. Imipramine, due to its potency in treating depression, can induce mania or hypomania in up to 25% of the patients maintained on imipramine. Imipramine is not as commonly used today due to the release of SSRIs, but is still a favorable drug for the treatment of major depression.