Atenolol

Medically Reviewed By University of Illinois Chicago Drug Information Group

Atenolol at a glance

Key highlights to know about atenolol are:

  • Atenolol is used to control high blood pressure, to help prevent angina (chest pain), and to increase survival after a heart attack. Atenolol may also be used to prevent migraine headaches and to treat alcohol withdrawal, heart failure, and an irregular heart rhythm, but these uses are “off-label,” meaning that the U.S. Food and Drug Administration (FDA) has not reviewed and approved it for this use.
  • Atenolol is available as a tablet that is administered by mouth.
  • Atenolol is typically a low-cost drug, defined in this article as costing less than $30/month.
  • Atenolol tablets are available as a generic and brand-name drug, called Tenormin.

Important safety warnings for atenolol

Atenolol has a black box warning (also called a boxed warning), which is the FDA’s most serious warning for drugs. These warnings alert doctors and patients that a drug has serious or life-threatening risks, including:

  • Discontinuation of atenolol warning: Do not abruptly stop atenolol. This can result in worsening symptoms of chest pain, a heart attack, or other serious effects on your heart. If your doctor decides to stop atenolol, follow the directions on how to slowly reduce the amount you take. This may take some time if you develop any heart symptoms, which may require you to continue taking atenolol for a period until you can stop completely.

Users of atenolol should be aware of these additional safety warnings:

  • Cardiac failure warning: Atenolol should not be used if you have a heart attack with uncontrolled heart failure. Atenolol can worsen heart failure that is not managed appropriately. For patients without heart failure, long-term use of atenolol may cause heart failure and should be treated appropriately. If heart failure continues despite treatment, your doctor may consider taking you off atenolol.
  • Calcium channel blocker warning: If you take verapamil or diltiazem, there is a chance that your heart rate will slow down too much. This is more likely to happen if you already have a condition that causes a low heart rate or problems with your heart.
  • Bronchospastic diseases warning: If you have a bronchospastic condition, such as asthma, your doctor will try medications other than atenolol to lower your blood pressure. Atenolol should only be used if those other medications do not work well. A low dose of atenolol will likely be used, and your doctor may have you keep a short-acting bronchodilator in case you need it. Be sure to report any symptoms to your doctor.
  • Major surgery warning: If you are scheduled to have major surgery, your doctor may consider stopping atenolol depending on the type of surgery and anesthetic that will be administered.
  • Diabetes and hypoglycemia warning: If you have diabetes and experience low blood sugar, atenolol might mask the feeling of a rapid heart rate that some people experience when their blood sugar is low. Other symptoms of low blood sugar (dizziness and sweating) are not affected by taking atenolol.
  • Thyrotoxicosis warning: Atenolol may block the rapid heart rate that can happen in people who have an overactive thyroid. Also, if you stop taking atenolol abruptly, this may affect your thyroid.
  • Untreated pheochromocytoma warning: Do not take atenolol if you have untreated pheochromocytoma (a tumor that develops near the kidneys that can cause high blood pressure and a rapid heart rate).
  • Pregnancy warning: Do not take atenolol if you are pregnant.

Talk with your doctor about these warnings in the context of your individual treatment plan and medical history.

What atenolol treats

This medication is used to:

  • Treat high blood pressure
  • Prevent angina (chest pain) symptoms
  • Improve survival in patients having a heart attack
  • Prevent migraine headaches as an off-label use (off-label use means this drug has not been reviewed or approved by the FDA for use in migraine)
  • Treat alcohol withdrawal as an off-label use (off-label use means that this drug has not been reviewed or approved by the FDA for use in alcohol withdrawal)
  • Treat heart failure as an off-label use (off-label use means that this drug has not been reviewed or approved by the FDA for use in heart failure)
  • Treat an irregular heart rhythm as an off-label use (off-label use means that this drug has not been reviewed or approved by the FDA for use in irregular heart rhythm)

Doctors sometimes prescribe medications for different uses. Ask your doctor or pharmacist for information about other uses of this medication.

How it works

Atenolol belongs to a class of medications called beta-blockers. It is one of the beta-blockers that is cardio-selective, which means that it works on areas related to the heart. Atenolol relaxes blood vessels and slows down the heart rate, which helps to lower blood pressure and reduce stress on the heart.

Atenolol works best when combined with a healthy lifestyle as recommended by your doctor.

Atenolol is available as a brand-name (Tenormin) and generic drug.

Side effects of atenolol

Atenolol side effects are possible and may go away with continued use. Serious side effects are rare.

Common side effects

The more common side effects that occur with atenolol include:

  • Cold arms and legs
  • Depression
  • Diarrhea
  • Dizziness
  • Low heart rate
  • Low blood pressure
  • Nausea
  • Tiredness

Serious side effects

Call your doctor right away if you have serious side effects. Seek emergency care (call 911) if you experience life-threatening symptoms, such as difficulty breathing; chest pain; loss of consciousness; sudden vision changes; or swelling of the face, mouth, tongue or throat.

Serious side effects and their symptoms can include the following:

  • Signs of worsening heart disease. Symptoms can include:
    • Shortness of breath
    • Swelling of the ankles, legs, hands or feet
    • Weight gain

Other side effects are possible. Talk to your doctor or pharmacist if you have any side effect that bothers you or that does not go away.

Costs of atenolol

Without insurance the generic and brand-name atenolol is typically a low-cost drug (defined as costing less than $30/month) You can check the out-of-pocket cash pay price for atenolol on prescription drug discount websites.

With insurance, prices can vary considerably. Individual health plans may have preferred drugs with better pricing. If the price of atenolol on your health plan is too expensive, ask your doctor or pharmacist if there is an equivalent drug you can substitute.

How atenolol may interact with other medicines

Atenolol may interact with other prescription and over-the-counter medications, vitamins, or herbal supplements you may be taking. To help avoid harmful interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbal supplements you are taking. To find out how this drug might interact with something else you are taking, talk to your doctor or pharmacist.

This is not a complete list of drugs that may interact with atenolol. However, examples of drugs that may interact with atenolol include:

Drugs used for high blood pressure (hypertension)

  • Calcium channel blockers (diltiazem [Cardizem, Cartia, Tiazac, Taztia], verapamil [Calan SR, Verelan]): An additive effect on blood pressure and heart rate can occur causing the blood pressure and/or heart rate to go too low.
  • Clonidine: Atenolol can worsen effects (causing an increase in blood pressure) that can occur when clonidine is being discontinued. Your doctor or pharmacist will decide how best for you to take these medications together or discontinue them when needed.
  • Reserpine: An additive effect on blood pressure and heart rate can occur causing the blood pressure and/or heart rate to go too low.

Drugs used to control irregular heart rhythm

  • Amiodarone: An additive effect on heart rate can occur causing the heart rate to go too low.
  • Digoxin: An additive effect on heart rate can occur causing the heart rate to go too low.
  • Disopyramide: When used with medications like atenolol, this drug has caused severe effects on the heart rate and has led to heart failure.

Nonsteroidal anti-inflammatory drugs (NSAIDs)

This class of drugs, such as indomethacin, can cause an increase in blood pressure and may reduce how well atenolol works. Talk to your doctor about the safe use of NSAIDs.

Injectable epinephrine

Beta-blockers, like atenolol, may interfere with how well injectable epinephrine works when used for treating severe allergic reactions (anaphylactic reactions). While taking atenolol, the severity of your allergic reactions may be worse.

Disclaimer: Since drugs interact differently in each person, this information is not guaranteed to include all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbal supplements, and over-the-counter drugs that you are taking.

Other atenolol alerts

This drug comes with additional alerts:

Impaired kidney function

The dose of atenolol will be lower if the function of your kidneys is reduced.

Elderly patients

The starting dose of atenolol may be lower in patients who are 65 years and older. The dose can be increased if needed depending on how well the medication is tolerated.

Circulation disorder

Atenolol should be used with caution if you have a circulation disorder (poor blood flow). Atenolol can make this worse. Tell your doctor about all your medical conditions to make sure Atenolol is safe for you to take.

Call your doctor right away if you have serious side effects. Seek emergency care (call 911) if you experience life-threatening symptoms, such as difficulty breathing; chest pain; loss of consciousness; sudden vision changes; or swelling of the face, mouth, tongue or throat.

For pregnant and breastfeeding women

Can I take atenolol when pregnant?

Atenolol can cause harm to your unborn baby if you are pregnant. Talk to your doctor about other medications that can be used.

Can I take atenolol when breastfeeding?

Atenolol does pass into breast milk and may have effects on your baby. Talk with your doctor about other options while breastfeeding.

How and when to take atenolol

Atenolol is a medication that is taken by mouth.Your doctor will determine the amount you need. The medication dose may be low when you first start and your doctor may slowly increase the dose depending on how you do and how much you need. You may start taking this does one time per day and may need to increase to two times per day based on your doctor's evaluation.It is important to know that atenolol takes time to work. This means you must continue to take the medication as prescribed. Your doctor can check to see if the medication is working and may change the dose if needed. It is very important that you do not stop taking this medication abruptly, as this can result in serious side effects. If your doctor decides to stop your atenolol, you will get specific instructions on how to slowly reduce the amount you take. This may take time, so be sure to ask your doctor about your questions or concerns.

Drug forms and strengths

  • Tablet
    • 25 mg
    • 50 mg
    • 100 mg

Dosage for high blood pressure

  • Usual dose
    • Start with 50 mg one time per day and increase to 100 mg if needed after 1 to 2 weeks.

Dosage for angina (chest pain)

  • Usual dose
    • Start with 50 mg one time per day and increase to 100 mg if needed after one week.
    • A dose of 200 mg one time per day may be needed.

Dosage for heart attack

  • Initiation
    • 50 mg 10 minutes after the last intravenous dose of atenolol administered in a healthcare setting. Another 50 mg should be administered 12 hours later.
  • Maintenance
    • 100 mg one time per day or 50 mg two times per day.  

If you miss a dose of atenolol

Take a missed dose as soon as you remember. However, if it is close to the time for your next dose, skip the missed dose, and take your regularly scheduled dose. Do not take a double dose to make up for a missed one.  

If you take too much atenolol

If you take too much atenolol, you have a higher risk of having side effects caused by this drug. Some, but not all, side effects can include extreme fatigue, trouble breathing, wheezing, slow heart rate, heart failure, low blood pressure, and low blood sugar.  If you think you have taken too much of this drug, call your doctor or local poison control center at 1-800-222-1222.

Seek emergency care (call 911) if you experience life-threatening symptoms, such as difficulty breathing; chest pain; loss of consciousness; sudden vision changes; or swelling of the face, mouth, tongue or throat.

Helpful tips when taking atenolol

Keep these considerations in mind if your doctor prescribes atenolol for you.

General

  • Atenolol should be taken as prescribed by your doctor.
  • To avoid serious side effects, do not stop taking atenolol on your own. Be sure to contact your doctor if you have concerns about taking atenolol.
  • It is important to follow a heart healthy lifestyle as recommended by your doctor.
  • Your doctor may ask you to check your blood pressure and heart rate regularly to determine if atenolol is working for you and to check if you are having side effects from atenolol.

Storage

  • Keep atenolol in its container and store at room temperature between 68⁰F to 77⁰F (20⁰C to 25⁰C). Do not store in an area that can get hot and moist, such as the bathroom.
  • Be sure the container is closed tightly and away from the reach and sight of children.
  • This medication should not be flushed down the toilet. Talk to your pharmacist or local garbage/recycling service about how to dispose of expired or unused medication.

Alcohol

Although there are no known interactions with atenolol and alcohol, your doctor may ask you to moderate your alcohol intake as part of a heart-healthy lifestyle.

Refills

Your doctor will write the number of authorized refills on your prescription. Talk with your pharmacist if you have questions about refills.

Travel

When planning to travel, keep these tips in mind for packing your medication:

  • Bring enough medication for the entire trip based on when your next dose is due.
  • Keep your medication with you, in a purse or a carry-on bag if flying. Do not put it into a checked bag in case you are separated from your luggage.
  • Keep your medications in their original containers, if possible, to reduce delays during airport or security screening. Keep all your medications together to expedite the process.
  • Avoid leaving your medication in a parked car for extended periods to protect it from extreme temperatures (hot or cold).

Availability

Many pharmacies stock this drug. When filling your prescription, you can call ahead to make sure your pharmacy carries it and has it in stock.

Medications similar to atenolol

Atenolol belongs to a class of medications called beta-blockers. Most beta-blockers are used to treat similar conditions, but some may be different. Other beta-blockers include acebutolol, betaxolol, bisoprolol, metoprolol (Kaspargo, Lopressor, Toprol), nadolol (Corgard), propranolol (Inderal), and timolol. Each medication has its own benefits and side effects profile. Your doctor will help determine the best option for you.

Discontinuing use of atenolol

Discontinuing atenolol abruptly can lead to serious side effects, including worsening symptoms of angina (chest pain), heart attack, or serious effects on your heart. Do not stop taking this drug unless instructed by your doctor.

Healthgrades Disclaimer:

This information is for educational purposes only. It should not be interpreted as medical advice, diagnosis or treatment. Healthgrades takes every effort to ensure this information is accurate and up to date. This content is not intended to cover all possible uses, side effects, warnings, precautions, allergic reactions, or drug interactions. Do not assume that the absence of such information means the medication is safe for your personal use. Always consult your doctor, pharmacist, or healthcare professional before taking or discontinuing any medication.

Medical Reviewer: University of Illinois Chicago Drug Information Group
Last Review Date: 2021 Sep 14
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Atenolol. MedlinePlus. National Library of Medicine, National Institutes of Health. https://medlineplus.gov/druginfo/meds/a684031.html
  2. Tenormin package insert. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=746db603-a6e1-4dc3-c2d8-92314419098c