Other Specified Obsessive-Compulsive and Related Disorder 263
or other appropriate laboratory evaluation. Symptoms that o ccur during or shortly after
(i.e., within 4 weeks of) substance intoxication  or withdrawal or after medication use may
be especially indicative of a substance/medi cation-induced obsessive-compulsive and re-
lated disorder, depending on the type, duration, or amount of the substance used.
Obsessive-compulsive and re lated disorders (primary). Obsessive-compulsive and re-
lated disorder due to another medical condition should be distinguished fr om a primary
obsessive-compulsive and related disorder. In primary mental disorders, no specific and
direct causative physiological mechanisms associated with a medical condition can be
demonstrated. Late age at onse t or atypical symptoms suggest the need for a thorough as-
sessment to rule out the diagnosis of obsessive-compulsive and related disorder due to an-
other medical condition. 
Illness anxiety disorder. Illness anxiety disorder is charac terized by a preoccupation with
having or acquiring a serious illness. In the case of illness anxiety disorder, individuals
may or may not have diagnosed medical conditions.
Associated feature of another mental disorder. Obsessive-compulsive and related symp-
toms may be an associated feature of another mental disorder (e.g., schizophrenia, an-
orexia nervosa). 
Other specified obsessive-compulsive and related disorder or unspecified obsessive-
compulsive and related disorder. These diagnoses are given if it is unclear whether the
obsessive-compulsive and rela ted symptoms are primary, substance-induced, or due to
another medical condition.
Other Specified Obsessive-Compulsive
and Related Disorder
300.3 (F42)
This category applies to presentations in which symptoms characteristic of an obsessive-