The purpose of this study is to evaluate the efficacy and safety of sublingual zolpidem presentation 5 mg in the induction of sleep in patients with primary insomnia.

• National study, phase IV, single-center, double-blind, randomized, parallel, controlled by zolpidem 10mg oral.
• Experiment duration: 93 days.
• 05 visits (days -3, 0, 15, 45 and 90).
• Efficacy will be evaluated for: Sleep induction and the maintenance of sleep.
• Adverse events evaluation.

Inclusion Criteria:

• Men or women aged between 20 and 64 years;
• Diagnosis of primary insomnia according to criteria defined by DSM-IV;
• Difficulty in maintaining sleep and waking up until 3 am;
• Not having used any psychoactive drug in the last 30 days prior to their inclusion in the study;
• Signature of IC.

Exclusion Criteria:

• Previous history of serious medical illness, neurological or psychiatric disorder;
• Allergy or hypersensitivity to zolpidem;
• Obstructive Sleep Apnea syndrome;
• Polysomnography with apnea and hypopnea index >10/hour or PLM >15/h;
• Other secondary sleep disorders;
• History of substance abuse or dependence;
• History of daily consumption of alcoholic beverages;
• Pregnancy, lactation or refusal to use safe contraceptive methods during the study.