Although treatment guidelines manifest that antidepressant response usually appear with a
delay of several weeks and suggest that treatment should be changed if a partial response has
not occurred after 4~6 week, these beliefs are no longer held by experts, and a new concept
is raised that the first 2 weeks of treatment may be a useful strategy for improving the
management of depression. New evidence indicates that early treatment response can be
predicted with high sensitivity after 2 weeks of treatment in patients with major depressive
Early improvement not only predicted response or remission, but also that lack of improvement
was associated with little chance of response if the treatment strategy remained unchanged.
The criterion of a 20% score reduction has been chosen as an early indicator of improvement
because it can be reliably measured in clinical trials and translates into a clinically
relevant change in the severity of depressive symptoms.
Antidepressants that enhance both serotonergic and noradrenergic neurotransmission may be
more effective than selective serotonin reuptake inhibitors (SSRIs) for acute-phase therapy
of major depressive disorder. As a noradrenergic and specific serotonergic antidepressant,
the antidepressive mechanism of mirtazapine is quite superior to SSRI and in particular has
been suggested to have a faster onset of action than SSRIs in MDD patients.
The aim of this study is to provide physicians with further information regarding early
improvement and the effectiveness of mirtazapine combined with a SSRI antidepressant therapy