Propranolol contains Propranolol, a beta blocker. It works by affecting the body’s response to nerve impulses, especially in the heart. It slows down your heart rate and makes it easier for the heart to pump blood around the body. This prevents arrhythmia, stabilizes blood pressure and prevents a heart attack. It also widens the blood vessels in the body for better blood flow, thereby preventing angina as well as migraine. The exact mechanism by which it prevents tremors is not known, but experts believe that Propranolol helps block the nerve impulses to the muscles responsible for tremors. Propranolol helps block the effects of the chemical messengers namely, adrenaline and noradrenaline, that are produced by the brain and are responsible for increasing your heart rate which makes you feel anxious. This way it helps with anxiety. While treating pheochromocytoma, Propranolol may be given to block the action of high-adrenaline hormones, to lower the risk of developing dangerously high blood pressure during surgery for removing the tumor.