Differences in These conditions
There is a significantly less amount of blood flow (in the left prefrontal cortex in particular) in ADHD children than is found in OCD children. This leads to less brain activity.
Perhaps the most telling clue indicating that someone has ADHD and OCD, or OCD rather than ADHD, is when a significant increase in OCD behaviors occurs after taking a stimulant medication such as Ritalin.
Medications such as an SSRI will usually cause a lessening of the symptoms of OCD while a stimulant will exacerbate them. If a person has both conditions, the OCD is treated first and then a stimulant can be reintroduced without causing an increase in OCD behaviors.
Someone with OCD doesn't entertain their obsessive thoughts or engage in their compulsive behaviors because they want to, but rather they feel they have to. So the repetitive rituals they perform speak more to OCD than ADHD. And the obsessive thoughts and compulsive behaviors are usually limited to specific ideations and tasks rather than the chronic and pervasive behaviors that are spread out on a much wider spectrum that is necessary to distinguish and diagnose the presence of ADHD.
The anxiety of a patient with OCD is primary to those thought and behaviors that they are obsessive about while the anxiety that is a symptom of ADHD, especially in children is secondary. It is a result of poor performance in everyday activities at work, school, and in social activities because the inattentiveness, over-stimulation, and impulsive behaviors are primary.
With all that said, the differentiation between ADHD obsessive compulsive conditions should be a little clearer. At the same time, it should be more apparent to recognize when the two conditions are comorbid. Self-diagnosis cannot be achieved merely by reading and applying the information here. You will need the help of a doctor to receive the proper diagnosis and treatment.
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