Colodyn transdermal patch is a kind of anti-hypertensive drugs, for alpha 2 agonist, it has a wide range of indications, the first is used to lower blood pressure, for patients with hypertension. The second can be used for children with ADHD and children with Tourette’s syndrome, such as obscene speech syndrome. The third can be used for substance withdrawal reactions, such as alcohol withdrawal and opioid withdrawal. The fourth can be used for anxiety disorders and post-traumatic stress disorder, as well as social phobia. The fifth can be used to alleviate excessive drooling caused by clozapine. The sixth can be used in combination with opioid substances for the treatment of cancer patients whose pain is not fully relieved by opioid medications.