 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  beta blockers. It works by blocking the action of certain natural chemicals in your body, such as epinephrine, on the heart and blood vessels. This effect lowers the heart rate, blood pressure, and strain on the heart. Chlorthalidone is a "water pill" (diuretic) and causes your body to get rid of extra salt and water. This effect may increase the amount of urine you make when you first start the medication. It also helps to relax the blood vessels so that blood can flow more easily.These medications are used together when 1 drug alone is not controlling your blood pressure. Your doctor may direct you to start taking the individual medications first, and then switch you over to this combination product if this is the best dose combination for you. How to use Tenoretic 50 See also Warning section. Take this medication by mouth with or without food as directed by your doctor, usually once daily. If you take this drug too close to bedtime, you may need to wake up to urinate. It is best to take this medication at least 4 hours before your bedtime. Consult your doctor or pharmacist if you have questions about your dosing schedule. Apple juice and orange juice may prevent your body from fully absorbing atenolol </s>