Tenormin is a prescription drug that contains the active ingredient atenolol. It is used to treat high blood pressure, angina, and certain types of heart attack. It works by slowing down the heart rate and relaxing the blood vessels so that blood can flow more easily through them. Tenormin can be taken orally in tablet form or injected directly into the bloodstream. It is important to follow your doctor's instructions when taking this medication, as it can have serious side effects if not taken properly. With proper use, Tenormin can help improve your overall health and reduce your risk of cardiovascular disease.