International suicide rate in developed countries averages 13.3 x 100.000 population, a rate increased from 1955 to 2001 by 3.3% which has decreased from 1990 to 2001 by 11.7%. This decline may be associated with an improved health care, including medical interventions, with the most relevant role is attributed to treatments with antidepressants. Most of the studies showing an inverse correlation between increased usage of antidepressants and decreased suicide rates are based on ecological designs which do not provide information on the individual level.

In order to prevent suicidal behavior it is fundamental to know that: [a] 90% of all suicides are associated with a psychiatric disorder, especially mood disorders that account for more than a half of all completed suicides; [b] the ratio of attempts to suicide in the general population is about 20:1, whereas the same ratio is about 5:1 in Bipolar Disorder (BPD) patients, showing higher lethality of suicide attempts. Indeed, the Standardized Mortality Ratio reaches the highest value (20; normal value = 1) in mood disorder patients among all psychiatric disorders, with little differences between BPD I and II, and Major Depressive Disorder.

Early interventions are important since suicide occurs in patients with BPD in the first years after illness onset. From a medical point of view, the use of antidepressants has not been associated with reduction of suicidal behavior. In BPD, the only treatment showing a consistent reduction of suicidal behavior is the maintenance therapy with lithium salts.