Guanfacine is used to treat both ADHD in children and hypertension in adults, and is also used to treat anxiety and other psychological disorders.

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And, in fact, CD is well known to occur simultaneously with other disorders, like ADHD, mood disorders, post-traumatic stress disorder, and anxiety.

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"We have to be careful not to confuse them with other conditions that can also cause problems in these realms like ADHD and social anxiety disorders, " he said.

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What really runs in families is a tendency toward mood disorders in general, as well as a number of other conditions, such as anxiety and risk of substance abuse.

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