Coexisting, or comorbid, conditions are two or more conditions which exist simutaneously. For example, an individual can have both ADHD and depression.
Treatment for coexisting conditions usually occurs at the same time, however, if one condition is causing more impairment than the other, that condition may be treated first and once stabilized, the other condition would be treated.
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Eileen Bailey is a freelance health writer. She is the author of What Went Right: Reframe Your Thinking for a Happier Now, Idiot’s Guide to Adult ADHD, Idiot’s Guide to Cognitive Behavioral Therapy, Essential Guide to Overcoming Obsessive Love, and Essential Guide to Asperger’s Syndrome. She can be found on Twitter @eileenmbailey and on Facebook at eileenmbailey.