(a ten' oh lole)

Brand Name(s): Tenormin^®, Tenoretic^® (as a combination product containing Atenolol and Chlorthalidone); also available generically

WHY is this medicine prescribed?

Atenolol is used alone or in combination with other medications to treat high blood pressure. It also is used to prevent angina (chest pain) and improve survival after a heart attack. Atenolol is in a class of medications called beta blockers. It works by relaxing blood vessels and slowing heart rate to improve blood flow and decrease blood pressure.

High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.

Are there OTHER USES for this medicine?

Atenolol is also used sometimes to prevent migraine headaches and to treat alcohol withdrawal, heart failure, and irregular heartbeat. Talk to your doctor about the possible risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

HOW should this medicine be used?

Atenolol comes as a tablet to take by mouth. For the treatment of high blood pressure and to prevent angina, it is usually taken once a day. To improve survival after a heart attack, it is usually taken once or twice a day. To help you remember to take atenolol, take it around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take atenolol exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor will probably start you on a low dose of atenolol and gradually increase your dose to allow your body to adjust to the medication. Talk to your doctor about how you feel and about any symptoms you experience during this time.

Atenolol controls high blood pressure and angina but does not cure them. It may take 1-2 weeks before you feel the full benefit of atenolol. Continue to take atenolol even if you feel well. Do not stop taking atenolol without talking to your doctor. If you suddenly stop taking atenolol, you may experience serious heart problems such as angina (chest pain), heart attack, or an irregular heartbeat. Your doctor will probably want to decrease your dose gradually. Your doctor will watch you carefully and will probably tell you to avoid physical activity during this time.

What SPECIAL PRECAUTIONS should I follow?

Before taking atenolol,

• tell your doctor and pharmacist if you are allergic to atenolol, any other medications, or any of the ingredients in atenolol tablets. Ask your pharmacist for a list of the ingredients.

• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking while you are taking atenolol. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• tell your doctor if you have a slow or irregular heart rate or heart failure. Your doctor may tell you not to take atenolol.

• tell your doctor if you have or have ever had asthma or other lung diseases; diabetes; hyperthyroidism (an overactive thyroid gland); pheochromocytoma (a tumor that develops on a gland near the kidneys and may cause high blood pressure and fast heartbeat); circulation problems; or heart or kidney disease. Also tell your doctor if you have ever had a serious allergic reaction to a food or any other substance.

• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking atenolol, call your doctor immediately.

• you should know that atenolol may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking atenolol. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.

• you should know that atenolol may increase the risk of hypoglycemia (low blood sugar) and prevent the warning signs and symptoms that would tell you that your blood sugar is low. Let your doctor know if you are unable to eat or drink normally or are vomiting while you are taking atenolol. You should know the symptoms of low blood sugar and what to do if you have these symptoms.

• you should know that if you have allergic reactions to different substances, your reactions may be worse while you are taking atenolol, and your allergic reactions may not respond to the usual doses of injectable epinephrine.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do IF I FORGET to take a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What SIDE EFFECTS can this medicine cause?

Atenolol may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• dizziness
• lightheadedness
• tiredness
• lack of energy
• drowsiness
• depression
• nausea
• diarrhea
• rash

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:

• shortness of breath
• wheezing
• swelling of the hands, feet, ankles, or lower legs
• unusual weight gain
• fainting
• rapid, pounding, or irregular heartbeat
• dry eyes

Atenolol may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

• lack of energy
• difficulty breathing
• wheezing
• slow heartbeat
• fainting
• swelling of the hands, feet, ankles, or lower legs
• unusual weight gain
• shakiness
• dizziness
• rapid heartbeat
• sweating or confusion
• blurred vision
• headache
• numbness or tingling of the mouth
• weakness
• excessive tiredness
• pale color
• sudden hunger

What OTHER INFORMATION should I know?

Keep all appointments with your doctor. Your blood pressure should be checked regularly to determine your response to atenolol. Your doctor may ask you to check your pulse (heart rate). Ask your pharmacist or doctor to teach you how to take your pulse. If your pulse is faster or slower than it should be, call your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™. © Copyright, 2024. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: August 15, 2023.