Clinical picture characterized by repeated periods of mania and depression, often occurring within a family. In the clearest form depressive and manic-periods alternate, with relatively normal periods between them. In other cases the patient simply undergoes periods of depression, generally associated with physical symptoms and delusions. The disease is probably rooted in heredity, but a particular event may set off an attack. Treatment is by medication. Neuroleptics are prescribed for delusions, and anti-depressive drugs for depression. Lithium salts help to correct mania, and are often used subcutaneously in calm periods to prevent further attacks. Admission to an institution is often necessary to protect the patient from acts which may later cause him difficulty. In manic depression the patient’s state of mind varies wildly without any particular cause.