Substance-induced sleep disorder is a mental health condition characterized by any one of a variety of sleep disturbances brought on by the use\/abuse of alcohol or a number of legal and illegal drugs. Depending on individual circumstances, the condition can produce insomnia (excessive sleeplessness), hypersomnia (excessive sleepiness), any one of several different sleep-related conditions known as parasomnias, or a mix of symptoms that feature aspects of insomnia, hypersomnia and\/or parasomnia. Some people develop substance-induced sleep disorder while intoxicated with a given causative substance, while others develop the condition during withdrawal when the body is trying to recover from the effects of substance use. Sleep Disorder Basics People with insomnia experience short or extended periods of time during which they have trouble falling asleep at bedtime or, alternatively, have trouble remaining asleep throughout their designated sleeping time. People with hypersomnia experience short or extended periods of time during which they have trouble remaining wakeful and alert throughout their designated waking hours. All parasomnias involve the presence of a mentally aroused state, normally associated with being awake, during sleeping hours. Conditions listed under this heading include sleepwalking disorder, nightmare disorder, and sleep terror disorder, as well as a more generalized condition called parasomnias not otherwise specified. In the United States, all sleep disorders receive their official classification from the American Psychiatric Association, which sets guidelines that practicing mental health professionals use when assessing their patients. According to these guidelines, true insomnia, hypersomnia, and parasomnia are distinct, unique mental disorders that have no basis in other types of mental disorders, or in any type of physical condition. They also have no basis in the use of any substance, whether that substance is a medication, illegally abused drug, or socially accepted drug. Substance-Induced Sleep Disorder Basics Substance-induced sleep disorder is a separate classification established by the American Psychiatric Association for substance-related conditions that mimic or strongly resemble the effects of the true sleeping disorders. Officially, a person affected by a substance-induced sleeping problem must have symptoms that are severe enough to disrupt normal daily function and prompt some form of medical intervention. In addition, the sleeping problem in question must clearly come from the use of a legal or illegal substance, and must appear either during intoxicated states involving the substance in question, or within 30 days after the end of an isolated bout or extended period of substance use. The American Psychiatric Association maintains diagnostic subcategories for the different substances that have the potential to trigger a sleep disorder. Legal substances with their own separate listings include alcohol, caffeine, amphetamine medications, opioid (also known as opiate or narcotic) medications, anxiety-reducing (anxiolytic) medications, and the sedative-hypnotic medication classes called barbiturates and benzodiazepines. Illegal substances with their own separate listings include heroin and other non-medical opioids, methamphetamine, and cocaine. All other substances with the potential to induce sleeping problems are grouped into a single subcategory titled "other (or unknown) substance." Specific Effects Different substances tend to produce different, characteristic sleep disorder-related symptoms. For instance, during the period of time immediately following peak intoxication, alcohol tends to produce both sleepiness and a state of reduced agitation known as sedation. However, when people intoxicated with alcohol fall asleep, they commonly experience alterations in their natural sleep cycles that produce poor or restless sleep, as well as nightmare-related parasomnia. Alcohol withdrawal can also produce poor or restless sleep; in cases involving heavy drinkers or alcoholics, these sleep disturbances sometimes continue for months or years, even if alcohol intake ceases. People intoxicated with amphetamines often experience some degree of insomnia; conversely, amphetamine withdrawal often produces symptoms of hypersomnia. People who abuse amphetamines or take high amphetamine doses prescribed by their doctors can develop serious distortions of their circadian rhythm, which is the internal "clock" that tells human beings when to sleep and when to wake. Other substances notable for their ability to produce insomnia during intoxication include cocaine and caffeine. In addition, cocaine withdrawal can easily produce varying degrees of hypersomnia. Considerations People who use substances capable of producing sleep disturbances also sometimes have undiagnosed symptoms of a true sleep disorder. During examination of their sleep-disordered patients, doctors have the difficult task of separating the effects of official insomnia, hypersomnia, and\/or parasomnia from the effects of a given legal or illegal substance. Factors that bear on this determination include the period of time during which sleeping problems occur, the level of substance use that occurred during this period, the intensity of the symptoms present in the affected individual, and the individual's prior history of both substance problems and sleeping problems. Substance-induced sleep disorder is likely in symptomatic people who used substances recently, have symptoms in line with the effects of the substance in question, and have no prior history of non-substance-related sleeping problems.