Antidepressant drugs that affect the availability of the neurotransmitter serotonin have been found especially useful in the treatment of:

The research shows that the use of antidepressant will be beneficial in a patient with major depression and obsessive-compulsive disorder. 

It should be clear that antidepressant works for depression, but some of them are used to treat OCD too. it has no effect on the antisocial, dissociative or schizophrenic patient though. The SSRI drugs that could be used for OCD would be sertraline, fluoxetine, fluvoxamine, and paroxetine. 

That is true! many fish species traveled to the u.s. because of it.