Antipsychotics are classified in two groups, the first generation (conventional, typical) and the second generation (modern, atypical). In the treatment of schizophrenia and psychoses antipsychotics of the second generation are the preferred choice due to their effectiveness and side effects profile. First and second generation antipsychotics are commonly used to treat acute mania. Moreover, second generation antipsychotics are used in the maintenance-treatment of bipolar disorder. Several second generation antipsychotics have been shown to be effective in the treatment of acute bipolar depression and as an augmentation-strategy in combination with an antidepressant in the treatment of unipolar depression. In clinical practice there is a big off-label use of antipsychotics, for example in the treatment of personality disorders. In addition to the oral dosage form, there exist two parenteral dosage forms of antipsychotics: quick-acting and long-acting injections. The side effects profile for first generation antipsychotics is characterized by extrapyramidal-motoric side effects. Second generation antipsychotics are, with respect to their effectiveness and side effects, very heterogeneous. Some substances present in the second generation grouping can lead to, in particular, an increased risk for weight gain and metabolic syndrome.