As insomnia is a common symptom caused by diverse disorders, treatment tools for the insomnia differ depending on the underlying cause. Hypnotics can be used for primary insomnia. As hypnotics show excellent short-term efficacy, they would be useful as short-term ( < 4 weeks) treatments for transient insomnia. There has been much controversy over long-term hypnotic use for chronic insomnia. Evidence supporting safety and efficacy of the long-term hypnotic use is insufficient. Therefore, rather than using hypnotics alone, non-pharmacological treatments are recommended more for chronic primary insomnia. Although various benzodiazepines have widely been used as hypnotics, there have been concerns over tolerance, rebound insomnia, dependency, cognitive decline and psychomotor slowness. In efforts to relieve these concerns, selective benzodiazepine agonists like zolpidem have been introduced as novel hypnotics. Sedating antidepressants, melatonin and anti-histamine have also been used in order to manage insomnia. However, their efficacy for primary insomnia has yet to be proven.