526 Substance-Related and Addictive Disorders
at onset with elevations in risk for other hallucinogen use disorder. However, patterns of
drug consumption have been found to differ by age at onset, with early-onset ecstasy users
more likely to be polydrug users than their later-onset counterpar ts. There may be a dis-
proportionate influence of use of specific hallu cinogens on risk of developing other hallu-
cinogen use disorder, with use of ecstasy/MDMA increasing the risk of the disorder
relative to use of other hallucinogens.
Little is known regarding the co urse of other hallucinogen use disorder, but it is generally
thought to have low incidence, low persistence, and high rates of recovery. Adolescents are es-
pecially at risk for using these drugs, and it is  estimated that 2.7% of youths ages 12–17 years
have used one or more of these drugs in the past 12 months, with 44 % having used ecstasy/
MDMA. Other hallucinogen use disorder is a disorder observed primarily in individuals
younger than 30 years, with rates vanishingly rare among older adults.
Risk and Prognostic Factors 
Temperamental. In adolescents but not consistently in adults, MDMA use is associated with
an elevated rate of other hallucinogen use di sorder. Other substance use disorders, particu-
larly alcohol, tobacco, and cannabis, and major depressive disorder are associated with ele-
vated rates of other hallucino gen use disorder. Antisocial personality disorder may be
elevated among individuals who use more than two other drugs in addition to hallucinogens,
compared with their counterparts with less exte nsive use history. The influence of adult anti-
social behaviors—but not conduct disorder or antisocial personality disorder—on other hal-