Primary objective:

1. To evaluate the efficacy of Zolpidem 5mg for 1 week in elderly patients with insomnia in China

Secondary objectives:

1. To evaluate the safety of Zolpidem 5mg for 3 weeks in elderly patients with insomnia in China.
2. To evaluate the efficacy of Zolpidem 5mg for 3 weeks in elderly patients with insomnia in China

Inclusion Criteria:

• Primary out-patient insomniac patient defined by DSM-IV criteria
• Insomnia history lasted at least 3 months , this history must include a self-reported usual sleep latency of 30 minutes or more and either 3 or more awakenings per night on average or a usual total sleep time of ≤6.5 hours

Exclusion Criteria:

• Usage of hypnotics within the previous 1-3 weeks before inclusion depending on the half-life of the hypnotics that would affect the study effect
• Concomitant usage of other hypnotics (benzodiazepines and Non-benzodiazepines) during the course if the study.
• Concomitant usage of the following Central Nervous System active medicine : antipsychotics , antidepressants ,anxiolytics, lithium and other psychotropic drugs.
• The score of Hamilton Depression Rating Scale (HAMD-24 ) more than 17.
• The score of Hamilton Anxiety Rating Scale (HAMA-14 ) more than 14.
• Patients having known hypersensitivity to Stilnox or any of the ingredients in the products
• Patient with severe respiratory insufficiency
• Patients suffering from sleep apnoea syndrome
• Patients with known severe hepatic (risk of encephalopathy) and /or renal insufficiency, or other severe organ diseases
• Patients suffering from severe myasthenia gravis
• Patients with the previous history of drug abuse, drug dependence and drug addiction
• Any other disease state or major psychiatric condition that might affect study result

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.