Propranolol belongs to the group of beta-blockers – drugs affecting your heart and circulation. If you are taking this medicine to treat high blood pressure make sure you do not stop the treatment unless your health care provider recommends you to do so. High blood pressure may display no symptoms and you may think you do not have a problem while you do. Also you will be most probably required to take propranolol for the rest of your life if you are using it for high blood pressure. Take a pill of propranolol whole, without breaking or crushing it to prevent the medicine from being released in excess.