Accumulating evidence suggests a role of G protein-coupled inwardly-rectifying potassium (GIRK) channel in the pathology of excitement of nerve, and the medicine with the action (like the Tipepidine Hibenzate) is expected as a new curative medicine of adolescent depression.

The purpose of this research is to confirm the effect by carrying out the additional dosage of the Tipepidine Hibenzate to the adolescent patients with depression.

If suggestion is obtained by this research about the effect on adolescent patients with depression of Tipepidine Hibenzate, it can contribute to development of the medical treatment of adolescent patients with depression.

[Inclusion Criteria]

1. Depressive Episode for ICD-10 criteria.
2. Patients are treated with antidepressants (SSRI ; Fluvoxamine, Paroxetine, Sertraline, Escitalopram, SNRI ; Milnacipran, Duloxetine, NaSSa; Mirtazapine), mood stabilizers (Lithium, Sodium Valproate, Carbamazepine, Lamotrigine), atypical antipsychotics (Risperidone, Olanzapine, Quetiapine, Perospirone, Aripiprazole, Blonanserin, Paliperidone) or not treated.
3. Patients are stable for 4-weeks for medication.

[Exclusion Criteria]

1. Patients with a previous hypersensitivity to Tipepidine Hibenzate.
2. Patients treated with typical antipsychotics and antidepressants except inclusion criteria 2. and mood stabilizers except inclusion criteria 2.
3. Pregnant or breast-feeding women