anxiety disorder is distinguished from generaliz ed anxiety disorder by the fact that a sub-
stance or medication (e.g., a drug of abuse, ex posure to a toxin) is judged to be etiologically
related to the anxiety. For example, severe anxi ety that occurs only in the context of heavy
coffee consumption would be diagnosed as caffeine-induced anxiety disorder.
Social anxiety disorder. Individuals with social anxiety disorder often have anticipa-
tory anxiety that is focused on upcoming social situations in which they must perform or
be evaluated by others, whereas individuals with generalized anxiety disorder worry,
whether or not they are being evaluated. 
Obsessive-compulsive disorder. Several features distinguish the excessive worry of
generalized anxiety disorder fr om the obsessional thoughts of obsessive-compulsive dis-
order. In generalized anxiety disorder the focus of the worry is about forthcoming prob-
lems, and it is the excessivene ss of the worry about future events that is abnormal. In
obsessive-compulsive disorder, the obsessions are inappropriate ideas that take the form of
intrusive and unwanted thou ghts, urges, or images. 
Posttraumatic stress disorder  and adjustment disorders. Anxiety is invariably pres-
ent in posttraumatic stress disorder. Generali zed anxiety disorder is not diagnosed if the
anxiety and worry are better explained by sy mptoms of posttraumatic stress disorder.
Anxiety may also be present in adjustment di sorder, but this residual category should be
used only when the criteria are not met for any other disorder (including generalized anx-
iety disorder). Moreover, in adjustment disorders, the anxi ety occurs in response to an
identifiable stressor within 3 months of the onset of the stressor and does not persist for
more than 6 months after the terminatio n of the stressor or  its consequences.