Primary objective: To show that the combination of Zolpidem + antidepressant therapy is more effective in the treatment of the secondary insomnia of depressive and dysthimic patients than antidepressant therapy alone in the acute phase of the disease.

Inclusion Criteria:

• Depressive and dysthimic patients in acute phase of mild to moderate severity
• Depressive and dysthimic patients suffering from secondary insomnia (DSM IV) recent antidepressant therapy (less than 1 week)

Exclusion Criteria:

• Regularly use of sleeping pills in the last 2-3 month
• Use of any sleeping pils in the last week
• Insufficient hepatic
• Myasthenia gravis
• Proven hypersensivity to Zolpidem
• Evidence of clinically relevant nervous system disorders (other neurologic/psychiatric diseases associated with depression)
• History of evidence of alcohol or drug abuse
• Evidence of clinically relevant cardiovascular, haematologic, hepatic, gastrointestinal, renal, pulmonary or endocrinologic diseases
• Abnormal snore
• Work an alternating shift
• Suffering from periodic leg movement disorder and sleep apnea