Benzodiazepines are effective as hypnotics, anxiolytics, anticonvulsants, myorelaxants and amnesics. Barbiturates such as phenobarbital were long used as anxiolytics and hypnotics. Corvalol may increase CNS depressant effect of other sedatives and hypnotics. Furthermore, melatonin, benzodiazepines hypnotics, and non-benzodiazepine hypnotics may be used to treat insomnia. Other cross-tolerant sedative hypnotics, such as barbiturates or alcohol, increase the risk of benzodiazepine dependence. The most commonly used class of hypnotics for insomnia are the benzodiazepines. Benzodiazepines are therefore not good hypnotics in the treatment of insomnia. Other definitions include ingested narcotics, hypnotics, and opioids. Barbiturates were introduced as hypnotics for patients with schizophrenia. Certain non-benzodiazepine drugs are used as hypnotics as well. These results suggested a relationship between abuse of sedatives or hypnotics and cerebral disorder. Commonly used hypnotics include thiopental, propofol and etomidate. Noscapine can increase the effects of centrally sedating substances such as alcohol and hypnotics. Gradual discontinuation of hypnotics leads to improved health without worsening of sleep. Fatigue and consumption of alcohol or hypnotics can cause sleep drunkenness as well.