When treating people suffering from major depression just one third achieve a complete remission of the symptoms, another one third have a partial response and the last third don't obtain any kind of response. According to STAR*D study, in less than 40% of the cases treated with one SIRS symptoms improved totally. When changing the first SIRS for another antidepressant, in less than 25% of the cases remission was obtained. the next strategy used was to combine two antidepressant, getting just 5,8% more remission and finally, the last step when treating major depression is the potentiation between antidepressant and other therapies (lithium, T3), obtaining 6,3% of accumulated rate of benefit.Quetiapine with its triple action mechanism (dopaminergic, serotoninergic and monoaminergic) have demonstrated when used in combination with antidepressants to obtain remission stadisticaly promoved when compared with the other strategies explained above.

To demonstrate using a clinical example the remission of major depression symptoms when combining quetiapine and other antidepressant after the non response even with electroconvulsive therapy (ECT).

Hamilton scale is used to measured the improvement of the case explained.

Quetiapine used with dual antidepressants after non response to ECT and other basic steps to treat major depression, reduces depression symptoms until total remission (Hamilton scale < 7).

Quetiapine used in combination improves totally major depression symptoms. It can be an other clinical strategy when symptoms appear resistant.