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Functional Consequences of 
Other Hallucinogen Use Disorder
There is evidence for long-term neurotoxic effects of MDMA/ecstasy use, including im-
pairments in memory, psychological function , and neuroendocrine function; serotonin
system dysfunction; and sleep disturbance; as  well as adverse effects on brain microvas-
culature, white matter maturation, and damage to axons. Use of MDMA/ecstasy may di-
minish functional connectiv ity among brain regions. 
Differential Diagnosis
Other substance use disorders. The effects of hallucinogens must be distinguished from
those of other substances (e.g., amphetamines ), especially because contamination of the
hallucinogens with other dr ugs is relatively common. 
Schizophrenia. Schizophrenia also must be ruled out,  as some affected individuals (e.g.,
individuals with schizophrenia who exhibit paranoia) may falsely attribute their symp-
toms to use of hallucinogens. 
Other mental disorders or medical conditions. Other potential disorders or conditions
to consider include panic disorder, depressive  and bipolar disorders, alcohol or sedative
withdrawal, hypoglycemia and other metabolic  conditions, seizure disorder, stroke, oph-
thalmological disorder, and central nervous sy stem tumors. Careful history of drug tak-
ing, collateral reports from family and friends (if possible), age, clin ical history, physical
examination, and toxicology reports should be useful in arriving at the final diagnostic de-
cision. 
Comorbidity
Adolescents who use MDMA/ecstasy and other ha llucinogens, as well as adults who have
recently used ecstasy, have a higher preval ence of other substance use disorders compared
with nonhallucinogen substance users. Individuals who use halluc inogens exhibit eleva-