418 Sleep-Wake Disorders
ing the withdrawal phase. Drugs like 3,4- methylenedioxymethamphetamine (MDMA; “ec-
stasy”) and related substances lead to restless and disturbed sleep with in 48 hours of intake;
frequent use of these compounds is associated with persisting symptoms  of anxiety, depres-
sion, and sleep disturbances, even  during longer-term abstinence.
Tobacco. Chronic tobacco consumption is associat ed primarily with symptoms of insom-
nia, decreased slow-wave sleep with a reductio n of sleep efficiency, and increased daytime
sleepiness. Withdrawal from tobacco can lead  to impaired sleep. Individuals who smoke
heavily may experience regular nocturnal awakenings caused by tobacco craving.
Other or unknown substances/medications. Other substances/medications may pro-
duce sleep disturbances, particularly medications that affect the central or autonomic
nervous systems (e.g., adrenergic agonists an d antagonists, dopamine agonists and antag-
onists, cholinergic agonists an d antagonists, serotonergic agonists and antagonists, anti-
histamines, corticosteroids). 
Development and Course
Insomnia in children can be identified by eith er a parent or the child. Often the child has a
clear sleep disturbance associated with initiation of a medication but may not report
symptoms, although parents observe the slee p disturbances. The use of some illicit sub-
stances (e.g., cannabis, ecstasy) is prevalen t in adolescence and early adulthood. Insomnia
or any other sleep disturbance encountered in  this age group should  prompt careful con-
sideration of whether the sleep disturbance is due to consumption of these substances.
Help-seeking behavior for the sleep disturbance in these age groups is limited, and thus