Consumer medicine information




Brand name


Active ingredient





Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using APO-Atenolol.

What is in this leaflet

Read this leaflet carefully before taking your medicine. This leaflet answers some common questions about atenolol. It does not contain all the available information. It does not take the place of talking to your doctor or pharmacist.

The information in this leaflet was last updated on the date listed on the last page. Some more recent information on the medicine may be available. You should ensure that you speak to your pharmacist or doctor to obtain the most up to date information on the medicine.

All medicines have risks and benefits. Your doctor has weighed the risk of you taking atenolol against the benefits it is expected to have for you.

If you have any concerns about taking this medicine, ask your doctor or pharmacist.

Keep this leaflet with the medicine. You may want to read it again.

What this medicine is used for

The name of your medicine is APO-Atenolol. It contains the active ingredient, atenolol.

Atenolol is used to:

  • lower high blood pressure (hypertension)
  • prevent angina (chest pain or discomfort)
  • treat an irregular heart beat or rhythm, also called arrhythmia
  • reduce your risk of heart complications following a heart attack.

All people have blood pressure. This pressure helps to push blood all around your body. Your blood pressure changes during the day, depending on how busy you are or how you are feeling.

You have hypertension (high blood pressure) when your blood pressure stays higher than is needed, even when you are calm and relaxed. Regular blood pressure checks are the only way of knowing that you have hypertension. There are usually no symptoms and you may feel fine. If hypertension is not treated, serious health problems such as stroke, heart disease and kidney failure may occur.

Atenolol helps to lower your blood pressure.

Angina is a pain or uncomfortable feeling in the chest, often spreading to the arms or neck and sometimes to the shoulders and back. This may be because there is not enough blood and oxygen getting to the heart. The pain of angina is usually brought on by exercise or stress, but can also occur at rest.

Atenolol helps prevent angina. It is not used to relieve a sudden attack of angina.

Irregular heart beat (arrhythmia):
Irregular heartbeat, also known as arrhythmia, means that there is a disturbance of the heart's normal rhythm or beat. Arrhythmias may be caused by a number of factors, including some heart diseases, an overactive thyroid gland, or chemical imbalances.

Atenolol helps restore your heart's normal rhythm.

Reducing heart complications after heart attack:
After a heart attack, you may have complications such as an irregular heart beat or an increased chance of having another heart attack.

Atenolol helps to prevent these complications from occurring.

Ask your doctor if you have any questions about why this medicine has been prescribed for you. Your doctor may have prescribed this medicine for another reason.

How it works

This medicine contains atenolol. Atenolol belongs to a group of medicines called beta-blockers. It decreases the heart's need for blood and oxygen and therefore reduces the amount of work the heart has to do. It widens the blood vessels in the body, causing blood pressure to fall. It also helps the heart to beat more regularly.

There is no evidence that this medicine is addictive.

It is available only with a doctor's prescription.

This medicine is not expected to affect your ability to drive a car or operate machinery, but make sure you know how it affects you before driving.

There is not enough information to recommend the use of this medicine for children.

Before you take this medicine

When you must not take it

Do not take this medicine if:

  1. you have or have had asthma (difficulty breathing, wheezing and coughing), bronchitis or other lung problems in the past.
  2. you have the following conditions:
  • a history of allergic problems, including hayfever. Symptoms of an allergic reaction may include skin rash, itchiness, shortness of breath, swelling of the face, lips or tongue, muscle pain or tenderness or joint pain
  • a very slow heart beat (less than 45-50 beats per minute)
  • a severe blood vessel disorder causing poor circulation in the arms and legs
  • certain other problems with your heart
  • phaeochromocytoma (a rare tumour of the adrenal gland), which is not being treated with other medicines
  • low blood pressure (hypotension)
  • too much acid in your blood (metabolic acidosis).
  1. you are receiving:
  • certain anaesthetics for medical or dental procedures
  • emergency treatment for shock or low blood pressure
  • any other beta blocker medicines
  1. you have an allergy or have had a hypersensitivity reaction to atenolol or any of the ingredients mentioned at the end of this leaflet, or any other beta blocker medicine
  2. you are pregnant or breast feeding, or if there is a chance that this may occur.
Your doctor will discuss the possible risks and benefits of using atenolol during pregnancy and breast feeding. Atenolol passes into breast milk and may therefore affect the breast-fed baby.

If you are not sure whether any of these apply to you, check with your doctor.

Do not use this product if the packaging is torn or shows signs of tampering

Do not use this product after the expiry date (EXP) printed on the pack. The medicine may not work as well after this date.

Do not use this product if the tablets change in appearance, colour or taste.

If it has expired or is damaged or does not seem quite right, return it to your pharmacist for disposal.

If you are not sure whether you should start taking atenolol, talk to your doctor.

Before you start to take it

Tell your doctor if you have allergies to:

  • any other medicines including eye drops, or other beta-blocker medicines.
  • any other substances, including foods, preservatives or dyes.
  • insect stings

Atenolol may make allergies worse or make them harder to treat.

Tell your doctor if you have or have had any medical conditions, especially the following:

  • heart problems
  • diabetes
  • an overactive thyroid (hyperthyroidism).
  • kidney problems
  • circulation problems
  • phaeochromocytoma, which is being treated with other medicines
  • a particular type of angina called prinzmetal angina or variant angina.
  • any medical condition affecting your blood vessels.

Tell your doctor if you plan to become pregnant or breast-feed.

If you have not told your doctor about any of the above, tell them before you start taking atenolol.

Taking other medicines

Tell your doctor or pharmacist if you are taking any other medicines, including any that you buy without a prescription from your pharmacy, supermarket or health food shop.

The medicines below may be affected by atenolol, or may affect how well it works. It is especially important that you tell your doctor if you are taking any of the following:

  • other beta-blocker medicines, including beta-blocker eye drops
  • medicines used to treat high blood pressure or angina, or example verapamil, diltiazem, nifedipine, clonidine
  • medicines to treat heart problems, such as disopyramide, quinidine, digoxin, amiodarone, guanethidine
  • insulin and tablets used to treat diabetes
  • certain medicines used to treat arthritis, pain, or inflammation, for example indomethacin or ibuprofen
  • cold remedies
  • medicines commonly used during surgery or in emergency situations (e.g. dopamine, adrenaline, noradrenaline and certain anaesthetics.

You may need to use different amounts of your medicine, or you may need to take different medicines.

Your doctor and pharmacist have more information on medicines to be careful with or avoid while taking atenolol.

Ask your doctor or pharmacist if you are not sure if you are taking any of these medicines.

How to take this medicine

Follow all directions given to you by your doctor or pharmacist carefully. They may differ from the information contained in this leaflet.

If you do not understand the instructions on the label, ask your doctor or pharmacist for help.

How much to take

Your doctor or pharmacist will tell you how many tablets you will need to take each day and how long to take them for. This depends on your condition and whether or not you are taking any other medicines.

The usual dose is from 50mg (1 tablet) up to 200mg (4 tablets) of atenolol daily. If your dose is 100mg or less, take it once a day. If you need to take more than 100mg (2 tablets), take half of your atenolol in the morning and the other half in the evening.

Angina or Irregular Heart Beat:
The usual dose is from 50mg (1 tablet) up to 100mg (2 tablets) taken as a single dose or half the dose in the morning and half at night.

Heart attack:
The usual dose is 50mg (1 tablet) of atenolol daily.

Certain people e.g. the elderly or those with kidney problems, may require a lower dose.

How to take it

Swallow the tablet(s) with a little fluid.

To break atenolol tablets into two equal halves place on a flat surface and press down on either side of break line with thumb and forefinger.

Your atenolol tablets may be provided in a calendar pack which is designed to remind you when to take this medication. To do this, take your first dose from the position marked "First Day". On the following day take the first tablet which is labelled with the appropriate day. When you have taken all doses in this pack, take your next atenolol prescription in the same way.

When to take it

Take your medicine at the same time every day. Taking your medicine at the same time each day will have the best effect. It will also help you remember when to take it.

It does not matter if you take it before or after food.

How long to take it for

Take your medicine every day.

Keep taking it until your doctor tells you to stop.

It helps to treat high blood pressure, irregular heartbeat, and heart attacks and prevent angina but does not cure it.

Make sure you have enough tablets to last over weekends and holidays.

Do not stop taking this medicine without checking with your doctor.

Your doctor may want you to gradually reduce the amount of atenolol you are taking. This should take place over a period of about 2 weeks before stopping completely. Do not stop suddenly as this may worsen your condition.

If you forget to take it

If you forget to take one or more doses of atenolol, and it is almost time for your next dose, skip the dose you missed and take your next dose when you are meant to. Otherwise, take it as soon as you remember, and then go back to taking your medicine as you would normally.

Do not take a double dose to make up for the dose that you missed. Do not take any more than your doctor prescribed for you. This may increase the chance of you getting an unwanted side effect.

If you are not sure what to do, ask your doctor or pharmacist.

If you have trouble remembering to take your medicine, ask your pharmacist for some hints.

If you take too much (overdose)

Immediately telephone your doctor or the Poisons Information Centre (Tel: 13 11 26 for Australia) or go to the Accident and Emergency Department at the nearest hospital, if you think that you or anyone else may have taken too much atenolol.

Do this even if there are no signs of discomfort or poisoning. You may need urgent medical attention.

If you take too much atenolol, you may faint, feel dizzy or light-headed, wheeze or have difficulty breathing. You may also have a very slow heart beat.

While you are taking this medicine

Things you must do

Always follow your doctor's instructions carefully.

Keep all of your doctor's appointments so that your progress can be checked.

Tell any other doctors, dentists and pharmacists who are treating you that you are taking atenolol.

Tell your doctor immediately if you become pregnant while taking atenolol.

If you are about to start taking a new medicine, remind your doctor and pharmacist that you are taking atenolol.

If you are going to have surgery (even at the dentist), tell your surgeon, anaesthetist or dentist that you are taking atenolol. Atenolol may affect some of the medicines used during surgery, or may cause your blood pressure to drop suddenly.

If you have to have any medical tests while you are taking atenolol, tell your doctor. Atenolol may affect the results of some tests.

Drink lots of water when exercising and during hot weather when taking atenolol, especially if you sweat a lot. If you do not drink enough water while taking atenolol, you may feel faint, light-headed or sick. The recommended healthy minimum water intake is 6-8 glasses a day.

Tell your doctor immediately if you have an allergic reaction to foods, medicines or insect stings. Atenolol can cause allergic reactions to be worse and harder to treat.

If you have diabetes, check your blood sugar level regularly and report any changes to your doctor. Atenolol may affect your diabetes. It may hide the symptoms of low blood sugar levels, such as a fast heart beat. It may also take longer for your blood sugar level to get back to normal even if you follow the usual treatment for diabetes. Your diabetic medicines may have to be changed or the doses

If you keep having angina attacks, or have more of them whilst taking atenolol, tell your doctor. Atenolol is used to help prevent angina, so your angina attacks should become less severe and occur less often.

Things you must not do

Do not stop taking your medicine, or lower the dosage, without checking with your doctor.

Do not take any new medicines with atenolol, unless your doctor has told you to.

Do not take your medicine to treat any other complaints unless your doctor or pharmacist tells you to.

Do not give this medication to anyone else, even if their symptoms seem similar to yours.

Things to be careful of

Be careful driving or operating machinery until you know how atenolol affects you. As with other beta blocker medicines, atenolol may cause dizziness, faintness, fatigue or light-headedness in some people. Make sure you know how you react to atenolol before you drive a car, operate machinery, or do anything else that could be dangerous if you are dizzy or light-headed. If you have any of these symptoms stop driving, operating machinery or performing dangerous tasks.

If you drink alcohol, dizziness or light-headedness may be worse.

If this problem gets worse or continues, talk to your doctor.

To help your body get used to the change in blood pressure, the following hints may be useful:

  • Stand up slowly when getting up from a chair or bed. This will allow your body get used to the change in position and blood pressure.
  • If you feel dizzy, sit or lie down until you feel better.
  • If you feel faint, sit down and put your head between your knees.

Be careful not to over-exercise when you first start taking atenolol. Atenolol helps prevent angina resulting from physical activity and exercise. You may be tempted to exercise too much. Talk to your doctor about how much exercise you can do.

Dress warmly during cold weather, especially if you will be outside for a long time (for example, when playing or watching sport in winter). Atenolol, like other beta-blocker medicines, may make you more sensitive to cold temperatures, especially if you have circulation problems. Beta-blockers tend to decrease blood circulation in the skin, fingers and toes.

Things that would be helpful for your blood pressure

The suggestions below may help your condition. Talk to your doctor or pharmacist about these measures and for more information.

Your doctor may advise you to limit your alcohol intake.

Your doctor may suggest losing some weight to help lower your blood pressure and help lessen the amount of work your heart has to do. Some people may need a dietician's help to lose weight.

Eat a healthy low-fat diet which includes plenty of fresh vegetables, fruit, bread, cereals and fish. Also eat less fat and sugar.

Your doctor may advise you to watch the amount of salt in your diet. To reduce your salt intake avoid using salt in cooking or at the table.

Side effects

Tell your doctor or pharmacist as soon as possible if you do not feel well while you are taking atenolol.

All medicines may have some unwanted side effects. Sometimes they are serious, but most of the time they are not. Your doctor has weighed the risks of using this medicine against the benefits he/she expects it will have for you.

Ask your doctor or pharmacist to answer any questions you may have.

Following is a list of possible side effects. Do not be alarmed by this list. You may not experience any of them.

Tell your doctor or pharmacist if you notice any of the following and they worry you:

  • stomach upsets such as diarrhoea, constipation, abdominal pain or heartburn (indigestion).
  • dry mouth, change in taste sensation
  • dizziness, headache or buzzing or ringing in the ears, difficulty hearing
  • slow or irregular heartbeat
  • dry eyes, problems with vision
  • runny or blocked nose
  • difficulty sleeping, nightmares, vivid dreams
  • skin reactions (e.g. rash, itching, worsening of psoriasis)
  • cold fingers and toes
  • increased hair loss.
  • tingling, "pins and needles"
  • sexual problems.
  • weakness, fatigue, lack of energy
  • feeling generally unwell

The above list includes the more common side effects. Mostly, these are mild.

Tell your doctor immediately if you notice any of the following:

  • confusion or disorientation
  • depression or mood changes or a worsening of these
  • unusual thoughts, hallucinations (seeing, feeling or hearing things that are not there).
  • dizziness or light-headedness (sometimes with fainting), especially on standing up, which may be due to low blood pressure.
  • coldness, burning, numbness or pain in the arms and/or legs.
  • irritated eyes (red, runny, itchy or dry), visual disturbances (e.g. blurred vision).
  • difficulty in speaking.
  • unsteadiness when walking.

These may be serious side effects. You may need urgent medical attention. Serious side effects are rare.

If any of the following happen, STOP taking atenolol, and tell your doctor immediately, or go to Accident and Emergency at your nearest hospital:

  • shortness of breath, sometimes with tiredness, weakness and reduced ability to exercise, swelling of the feet or legs due to fluid build up
  • unusual bruising or bleeding
  • chest pain, changes in heart rate (fast, slow or irregular), palpitations
  • chest tightness, wheezing, rattly breathing
  • yellowing of the skin and/or eyes (jaundice)
  • signs of a serious allergic reaction such as shortness of breath, wheezing or troubled breathing, swelling of the face, lips, mouth, throat or tongue which may cause difficulty in swallowing or breathing, or swelling of other parts of the body

These are very serious side effects. You may need urgent medical attention or hospitalisation. These side effects are very rare.

Other side effects not listed above may occur in some patients.

Tell your doctor or pharmacist if you notice anything that is making you feel unwell.

Storage and disposal


Keep atenolol in the original packaging until you need to take it. If you take the tablets out of their original packaging, they may not keep well.

Keep your tablets in a cool, dry place where the temperature will stay below 25°C.

Do not store the tablets or any other medicines in the bathroom or near a sink.

Do not leave the tablets in the car on hot days or on windowsills. Heat and dampness can destroy some medicines.

Keep the tablets where children cannot reach them. A locked cupboard at least one-and-a-half metres above the ground is a good place to store medicines.


If your doctor or pharmacist tells you to stop taking this medicine or if it has passed its expiry date, ask your pharmacist what to do with any medicine that is left over.

Where to go for further information

Pharmaceutical companies are not in a position to give people an individual diagnosis or medical advice. Your doctor or pharmacist is the best person to give you advice on the treatment of your condition.

Product description

What APO-Atenolol looks like

50 mg tablets: white to off white, circular biconvex film coated tablets with "50" embossed on one side and break line on other side.

Blister packs or bottles containing 30 tablets.

*Not all pack sizes and/or types may be available.


Active Ingredient:

Each tablet contains 50mg of atenolol.

It also contains the following inactive ingredients:

  • magnesium stearate
  • maize starch
  • sodium lauryl sulphate
  • colloidal anhydrous silica
  • sodium starch glycollate type A
  • magnesium carbonate hydrate
  • Hypromellose
  • macrogol 6000
  • titanium dioxide
  • purified talc

Australian Registration Numbers

New formulation

APO-Atenolol 50 mg tablets (blister): AUST R 214939

APO-Atenolol 50 mg tablets (bottle): AUST R 214940


Apotex Pty Ltd
16 Giffnock Avenue
Macquarie Park NSW 2113

APO and APOTEX are registered trade marks of Apotex Inc.

This leaflet was prepared in
December 2020

Published by MIMS January 2021


Brand name


Active ingredient





1 Name of Medicine


2 Qualitative and Quantitative Composition

Each APO-Atenolol tablet contains atenolol 50 mg as the active ingredient.

3 Pharmaceutical Form

APO-Atenolol 50 mg tablets are intended for oral administration.
White to off-white, circular biconvex film coated tablets with "50" embossed on one side and break line on other side.

4 Clinical Particulars

4.1 Therapeutic Indications

All grades of hypertension, including hypertension of renal origin.
Frequent disabling angina without evidence of cardiac failure.
Cardiac arrhythmias (maintenance treatment of supraventricular and ventricular arrhythmias which have been controlled with other intravenous agents, including those associated with acute myocardial infarction).
Myocardial infarction: late intervention (beta-blockers class effect greater than 12 hours after onset of chest pain).

4.2 Dose and Method of Administration



Therapy should be initiated with atenolol 50 mg daily. This may be increased each week in daily doses of 50 mg up to a maximum of 200 mg. Where patients are controlled on daily doses of 50 to 100 mg this may be given once daily. Doses above 100 mg daily should be given on a divided basis. Where necessary, a further reduction in blood pressure may be achieved by combining atenolol with other antihypertensive agents.
Patients can be transferred to atenolol from other antihypertensive treatments with the exception of clonidine (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions, Clonidine).

Angina pectoris.

Therapy should be initiated with atenolol 50 mg daily. This may be increased if required to 100 mg daily given as a single or divided dose. It is unlikely that additional benefit will be gained by increasing the dose.

Cardiac dysrhythmias.

50 mg to 100 mg daily (for controlled cardiac dysrhythmias).

Acute myocardial infarction - late intervention (> 12 hours from onset of chest pain).

Atenolol has been shown to reduce infarct size, reduce the incidence of ventricular arrhythmias, reduce the need for opiate analgesics and reduce mortality in the first 7 post-infarction days, most of the benefit being in the first 48 hours.
Data from other beta-blocker trials suggest that there is a significant reduction in mortality and a reduced incidence of non-fatal reinfarction if the beta-blocker is continued for one to three years. Hence, maintenance oral therapy of atenolol 50 mg daily is recommended for one to three years following myocardial infarction, beginning after early intervention with other agents, or immediately in those patients who present more than 12 hours after suffering an acute myocardial infarction.

Impaired renal function.

Since atenolol is excreted via the kidneys, dosage should be adjusted in cases of severe impairment of renal function. No significant accumulation of atenolol occurs at a creatine clearance greater than 35 mL/min/1.73 m2 (normal range is 100 to 150 mL/min/1.73 m2). For patients with a creatine clearance of 15 to 35 mL/min/1.73 m2 (equivalent to serum creatinine of 300 to 600 micromol/L), the oral dose should be 50 mg daily or 100 mg on alternate days.
For patients with a creatinine clearance less than 15 mL/min/1.73 m2 (equivalent to serum creatinine greater than 600 micromol/L). The oral dose should be 50 mg on alternate days or 100 mg every fourth day.
Patients on haemodialysis should be given 50 mg orally after each dialysis: this should be done under hospital supervision as marked falls in blood pressure can occur.


Similarly, dosage requirements in the elderly may need to be reduced, especially in patients with impaired renal function.


There is no experience with atenolol in children.

4.3 Contraindications

Bronchospasm. Beta-adrenergic blockade of the smooth muscle of bronchi and bronchioles may result in an increased airways resistance. These drugs also reduce the effectiveness of asthma treatment. This may be dangerous in susceptible patients. Therefore, beta-blockers are contraindicated in any patient with a history of airways obstruction or tendency to bronchospasm. Use of cardioselective beta-blockers can also result in severe bronchospasm. If such therapy must be used, great caution should be exercised. Alternative therapy should be considered.
Congestive heart failure.
Allergic disorders (including allergic rhinitis) which may suggest a predisposition to bronchospasm.
Right ventricular failure secondary to pulmonary hypertension.
Significant right ventricular hypertrophy.
Sinus bradycardia (less than 45 to 50 beats/minute).
Sick sinus syndrome.
Second and third degree atrioventricular block.
Shock (including cardiogenic and hypovolaemic shock).
Metabolic acidosis.
Severe peripheral arterial circulatory disturbances.
Untreated phaeochromocytoma.
Anaesthesia with agents that produce myocardial depression (e.g. ether, chloroform, cyclopropane).
Pregnancy and lactation (see Section 4.4 Special Warnings and Precautions for Use; Section 4.6 Fertility, Pregnancy and Lactation, Use in lactation).
Hypersensitivity to the drug.

4.4 Special Warnings and Precautions for Use

Cardiac failure.

Beta-blockade depresses myocardial contractility and may precipitate cardiac failure in some patients with a history of cardiac failure, chronic myocardial insufficiency or unsuspected cardiomyopathy as may occur in chronic alcoholism. In patients without a history of cardiac failure, continuing depression of the myocardium may lead to cardiac failure. If signs of cardiac failure are present, the patient should be fully digitalised and/or given an ACE inhibitor or vasodilators with or without a diuretic and carefully monitored. If cardiac failure persists, the beta-blocker should be withdrawn (see Abrupt withdrawal of therapy, below).


Although congestive heart failure has been considered to be a contraindication to the use of beta-blockers, there is growing literature on the experimental use of beta-adrenergic blocking drugs in heart failure. As further trials are needed to identify which patients are most likely to respond to which drugs, beta-blockers should not normally be prescribed for heart failure outside of specialist centres.

Abrupt withdrawal of therapy.

Care should be taken if beta-blockers have to be discontinued abruptly in patients with coronary artery disease. Severe exacerbation of angina and precipitation of myocardial infarction and ventricular arrhythmias have occurred following abrupt discontinuation of beta-blockade in patients with ischaemic heart disease. Therefore, it is recommended that the dosage be reduced gradually over a period of about 8 to 14 days during which time the patient's progress should be reassessed. The drug may be reinstituted temporarily if the angina worsens. If the drug must be withdrawn abruptly, close observation is required. In the peri-operative period, beta-blockers should not be withdrawn unless indicated.

History of anaphylactic reaction.

While taking beta-adrenoreceptor blocking drugs, patients with a history of anaphylactic reaction to a variety of allergens may have a more severe reaction on repeated challenge. Such patients may be unresponsive to the usual doses of adrenaline used to treat the allergic reactions.

First degree heart block.

Due to its negative effect on conduction time, caution must be exercised if atenolol is given to patient with first degree heart block.

Peripheral circulation.

Beta-blockade may impair the peripheral circulation and exacerbate the symptoms of peripheral vascular disease.

Prinzmetal angina.

There is a risk of exacerbating coronary artery spasm if patients with Prinzmetal or variant angina are treated with a beta-blocker. If this treatment is essential, it should only be undertaken in a coronary or intensive care unit.

Euthyroid hyperthyroxinaemia.

The effects of beta-blockers on thyroid hormone metabolism may result in elevations of serum free thyroxine (T4) levels. In the absence of any signs or symptoms of hyperthyroidism, additional investigation is necessary before a diagnosis of thyrotoxicosis can be made.

Use in acute myocardial infarction.

In addition to the contraindications listed (see Section 4.3 Contraindications), patients with the following conditions are not suitable for treatment with atenolol:
(a) Systolic blood pressure less than 120 mmHg (systolic blood pressure less than 120 mmHg in combination with a heart rate greater than 90 beats/min has a particularly poor prognosis).
(b) First degree atrioventricular block. There is an increased incidence of cardiogenic shock (and need for inotropes), complete heart block and cardiovascular death in these patients, following atenolol.
Patients with atrial fibrillation following myocardial infarction, who were treated with atenolol, also had increased cardiovascular mortality compared with those not treated with atenolol. It is suggested that such patients be digitalised before atenolol therapy is commenced.


If a treated patient develops symptoms which may be attributable to a slow heart rate, the dose may be reduced.

Anaesthesia and the peri-operative period.

Beta-blockade may have beneficial effects in decreasing the incidence of arrhythmias and myocardial ischaemia during anaesthesia and the post-operative period. It is currently recommended that maintenance beta-blockade be continued peri-operatively. The anaesthetist must be made aware of beta-blockade because of the potential for interactions with other drugs, resulting in severe bradyarrhythmias and hypotension, the decreased reflex ability to compensate for blood loss, hypovolaemia and regional sympathetic blockade, and the increased propensity for vagal-induced bradycardia. Incidents of protracted severe hypotension or difficulty restoring normal cardiac rhythm during anaesthesia have been reported. Modern inhalational anaesthetic agents are generally well tolerated, although older agents (ether, cyclopropane, methoxyflurane, trichlorethylene) were sometimes associated with severe circulatory depression in the presence of beta-blockade.


Beta-blockers affect glucose metabolism and may mask some important premonitory signs of acute hypoglycaemia, such as tachycardia.
In patients with insulin or non-insulin dependent diabetes, especially labile diabetes, or with a history of spontaneous hypoglycaemia, beta-blockade may result in the loss of diabetic control and delayed recovery from hypoglycaemia. The dose of insulin or oral hypoglycaemic agent may need adjustment.

Other metabolic effects.

Beta-adrenoreceptors are involved in the regulation of lipid as well as carbohydrate metabolism. Some drugs affect the lipid profile adversely although the long-term clinical significance of this change is unknown and the effect appears to be less for drugs with intrinsic sympathomimetic activity.


In patients with this condition, an alpha-blocking drug (e.g. phentolamine/ phenoxybenzamine) should be administered before the beta-blocker to avoid exacerbation of hypertension.

Eye and skin reactions.

Various skin rashes and conjunctival xerosis have been reported with beta-blockers. Cross reactions may occur between beta-blockers, therefore substitutions within the group may not necessarily preclude occurrence of symptoms.
During long-term treatment with the beta-blocking drug, practolol, a specific rash bearing a superficial resemblance to psoriasis was occasionally described. In a number of patients affected, this rash was accompanied by adverse effects on the eye (xerophthalmia and/or keratoconjunctivitis) of varying severity. This condition is called the oculomucocutaneous syndrome or practolol syndrome. In a few patients, these eye changes occurred independently of a skin rash. On rare occasions, serous otitis media, sclerosing peritonitis, pericarditis and pleurisy have been reported. Although the practolol syndrome has not been observed in patients taking other beta-blockers, the possibility of such side effects occurring should be borne in mind.
More recently an association between Peyronie's disease (a fibrosing induration of the penis) and various beta-blockers has been suggested but is not proven.

Allergic conditions.

These may be exaggerated by beta-blockade (e.g. allergic rhinitis during the pollen season and allergic reactions to bee and wasp stings). Beta-blockers should be avoided if there is a risk of bronchospasm.


Because beta-blockers may mask the clinical signs of developing or continuing hyperthyroidism, resulting in symptomatic improvement without any change in thyroid hormone status, special care should be exercised in those patients who are hyperthyroid and are also receiving beta-blockers.

Use in renal impairment.

In patients with severe renal disease, haemodynamic changes following beta-blockade may impair renal function further. Beta-blockers which are excreted mainly be the kidney, may require dose adjustment in patients with renal failure.

Significant cardiomegaly.

Use in the elderly.

See Section 4.2 Dose and Method of Administration.

Paediatric use.

No data available.

Effects on laboratory tests.

No data available. See Section 4.8 Adverse Effects (Undesirable Effects), Biochemical abnormalities.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Concomitant therapy with calcium antagonists.

The concomitant use of beta-blockers and calcium antagonists with myocardial depressant and sinus node activity, e.g. verapamil and to a lesser extent diltiazem, may cause hypotension, bradycardia and asystole, particularly in patients with impaired ventricular function and/or sinoatrial or atrioventricular conduction abnormalities. Extreme caution is required if these drugs have to be used together.
The dihydropyridine calcium antagonists (e.g. nifedipine) have a weaker myocardial depressant effect and can be administered cautiously with beta-blockers. If excessive hypotension develops, the calcium antagonist should be stopped or the dosage reduced.

Antiarrhythmic drugs.

Care should be taken when prescribing beta-blockers with antiarrhythmic drugs. Class IA anti-arrhythmic drugs (e.g. disopyramide) and the Class III agent, amiodarone may have a potentiating effect on arterial conduction time and induce negative inotropic effect; this is seen less frequently with quinidine; class IB agents, tocainide, mexiletine and lignocaine; class IC agents, flecainide and propafenone (not available in Australia) and the class IV antiarrhythmic agents.

Use of catecholamine depleting agents.

Concomitant use of drugs such as reserpine and guanethidine requires careful monitoring since the added effect of beta-blockade may produce an excessive reduction of the resting sympathetic nervous tone.


Concurrent use of beta-blockers and clonidine should be avoided because of the risk of adverse interaction and severe withdrawal symptoms. If administered concomitantly, the clonidine should not be discontinued until several days after the withdrawal of the beta-blocker.

Insulin and oral hypoglycaemics.

See Section 4.4 Special Warnings and Precautions for Use, Diabetes.


Anaesthetics, such as ether, chloroform, cyclopropane and methoxyflurane, are contraindicated with atenolol (see Section 4.4 Special Warnings and Precautions for Use, Anaesthesia and the peri-operative period).

Digitalis / digitalis glycosides.

Digitalis/digitalis glycosides and beta-blockers are commonly used together, although there have been reports of excessive bradycardia when beta-blockers are used to treat digitalis intoxication.

Sympathomimetic agents.

Concomitant use of sympathomimetic agents, e.g. adrenaline, may counteract the effects of beta-blockers.

Prostaglandin synthetase inhibitors.

Concomitant use of prostaglandin synthetase inhibiting drugs, e.g. ibuprofen and indomethacin may decrease the hypotensive effects of beta-blockers.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

No data available.
(Category C)
Category C - Definition: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human foetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.
Neonates born to mothers who are receiving atenolol at parturition or breast-feeding may be at risk of hypoglycaemia and bradycardia. Therefore, during the later stages of pregnancy and parturition, this drug should only be given after weighing the needs of the mother against the risk to the foetus.
Atenolol crosses the placental barrier in pregnant women, and under steady state conditions, maternal and foetal blood levels of atenolol are approximately equal.
No studies have been performed on the use of atenolol in the first trimester and the possibility of foetal injury cannot be excluded. Atenolol has been used under close supervision for the treatment of hypertension in the third trimester. Administration of atenolol for longer periods to pregnant women in the management of mild to moderate hypertension has been associated with intrauterine growth retardation.
The use of atenolol in women who are, or may become, pregnant requires that the anticipated benefit be weighed against the possible risks, particularly in the first and second trimesters. In general, β-blockers reduce placental perfusion, which has been associated with growth retardation, intrauterine death, abortion and early labour.
Atenolol has been shown to produce a dose related increase in embryo/ foetal resorptions in rats at doses equal to or greater than 50 mg/kg. Although similar effects were not seen in rabbits, the compound was not evaluated in rabbits at doses above 25 mg/kg.
There is significant accumulation of atenolol in breast milk. Neonates born to mothers who are receiving atenolol at parturition or breast-feeding may be at risk of hypoglycaemia and bradycardia. Caution should be exercised when atenolol is administered to breastfeeding women and the infant should be regularly assessed for signs of beta-blockade.

4.7 Effects on Ability to Drive and Use Machines

Use is unlikely to result in any impairment of the ability of patients to drive or operate machinery. However, it should be taken into account that occasionally dizziness or fatigue may occur.

4.8 Adverse Effects (Undesirable Effects)

Adverse effects reported in clinical trials of atenolol are mainly attributable to pharmacological actions. The adverse effects listed below have been observed in patients in clinical trials who have received dosages of about 100 mg/day. It is not possible to give percentage incidences for each reaction, but if all mild and transient reactions are included as well as more serious ones, up to 10% of patients may experience some form of adverse reaction.

More common reactions.


Disturbances including indigestion, constipation, dry mouth.

Nervous system.

Fatigue, dizziness.


Wheezing, bronchospasm (see Section 4.3 Contraindications).

Less common reactions.

Biochemical abnormalities.

Increases in AST, blood urea and serum creatine have been reported.


Bradycardia, left ventricular insufficiency, postural hypotension (which may be associated with syncope), Raynaud's phenomenon, cold extremities, deterioration in heart failure, heart block. Intermittent claudication may occur if already present.


Rash, alopecia, psoriasiform skin reaction, exacerbation of psoriasis.




Elevations of transaminase levels have been seen infrequently; rare cases of hepatic toxicity including intrahepatic cholestasis have been reported.





Nervous system.

Vivid dreams, paraesthesia, tinnitus, vertigo, malaise, headache, insomnia, mood changes, nightmares, confusion.


Dry eyes, visual disturbances.


Hallucinations, depression, psychoses.


Asthma, dyspnoea, nasal congestion.


Thrombocytopenia, purpura. An increase in ANA (Antinuclear Antibodies) has been observed, however, the clinical relevance of this is not clear.

Severe or life-threatening reactions.

Myocardial insufficiency may require treatment with digitalis and diuretics. Bradycardia may respond to atropine. Bronchospasm may be reversed with a beta2-stimulant. Hypotension, if severe, may require use of a vasopressor.

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at

4.9 Overdose


Overdosage has not been reported with atenolol but in overdosage with other beta-blocking agents, severe bradycardia and hypotension are commonly found. Acute heart failure and bronchospasm may also occur.


Severe bradycardia.

Atropine 1 to 2 mg intravenously may be used to induce vagal blockade. If bradycardia persists, intravenous isoprenaline (25 microgram initially) or orciprenaline (0.5 mg given by slow intravenous injection) may be given. In refractory cases, the use of a cardiac pacemaker may be considered.


Severe hypotension should respond to a sympathomimetic amine such as noradrenaline. In refractory cases, the use of glucagon hydrochloride should be considered.


Therapy with a beta2-stimulant such as salbutamol or terbutaline or therapy with aminophylline may be considered.

Acute cardiac failure.

Conventional therapy with digitalis, diuretics and oxygen should be instituted immediately. In refractory cases, the use of intravenous isoprenaline, followed if necessary by glucagon hydrochloride or intravenous aminophylline, should be considered.
For information on the management of overdose, contact the Poison Information Centre on 131126 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Atenolol is a beta-adrenoceptor blocking agent structurally related to propranolol and differing from it by substitution on the aromatic ring. It acts preferentially on beta-receptors in the heart. Selectively decreases with increasing dose. It has little intrinsic sympathomimetic activity and no membrane stabilising activity. Atenolol is a racemic mixture and its activity resides in the S(-) enantiomer. It reduces raised blood pressure by an unknown mechanism and also inhibits exercise induced tachycardia and decreases plasma renin concentration. It causes slight airways obstruction but less than that seen with non-selective beta-blockers. The inhibition of exercise induced tachycardia is correlated with blood levels but there is no correlation between plasma concentrations and antihypertensive effect. Atenolol is effective and well tolerated in most ethnic populations although the response may be less in Afro-Caribbean black patients.
The possible mechanism of the anti-anginal activity of atenolol appears to be due to a reduction in left ventricular work and oxygen utilisation resulting (mainly) from the decrease in heart rate and contractility.
The anti-arrhythmic effect of atenolol is apparently due to its anti-sympathetic effect. There is no evidence that membrane stabilising activity or intrinsic sympathomimetic activity are necessary for anti-arrhythmic efficacy. By its anti-sympathetic effect, atenolol depresses sinus node function, atrioventricular node function and prolongs atrial refractory periods. It has no direct effect on electrophysiological properties of the His-Purkinje system.
Because of their negative inotropic effects, beta-adrenoreceptor blocking agents should be avoided in uncontrolled heart failure.

Clinical trials.

No data available.

5.2 Pharmacokinetic Properties


Although absorption of atenolol is variable and incomplete (40 to 60%), the virtual lack of hepatic/ liver metabolism results in relatively consistent systemic bioavailability compared to other beta-blockers.


Blood levels in humans peak two to four hours after a single 100 mg oral dose and are of the order of 0.4 to 0.9 microgram/mL. Blood levels are consistent and the levels after chronic oral administration are in good agreement with those predicted from single dose results.


The drug is distributed throughout the body tissues and less than 10% of the dose is metabolised, the minor urinary metabolite identified being a hydroxylated derivative.


The main route of elimination is renal excretion. The plasma half-life, measured by blood level decay or urinary build-up is approximately 7 to 9 hours. In patients with impaired renal function, there is a progressive prolongation of the half-life. In patients with normal renal function, the therapeutic effect (i.e. control of raised blood pressure) lasts for at least 24 hours following a 50 mg oral dose.

5.3 Preclinical Safety Data


No data available.


No data available.

6 Pharmaceutical Particulars

6.1 List of Excipients

Each tablet contains the following inactive ingredients: magnesium stearate, maize starch, sodium lauryl sulphate, colloidal anhydrous silica, sodium starch glycollate type A, magnesium carbonate hydrate, hypromellose, macrogol 6000, titanium dioxide, purified talc.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine. See Section 4.5 Interactions with Other Medicines and Other Forms of Interactions.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Store below 25°C. Protect from light and moisture.

6.5 Nature and Contents of Container

Blister pack (PVC/PVDC/Alu) of 10, 14, 28 and 30 tablets. AUST R 214939.
Bottle pack (HDPE) of 30, 100, 250 and 500 tablets - 100, 250 and 500 tablets packs are for dispensing only. AUST R 214940.
Not all pack types and/or pack sizes may be available.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Atenolol is a white or almost white powder, sparingly soluble in water, soluble in ethanol, slightly soluble in methylene chloride and practically insoluble in ether.

Chemical structure.

Chemical Name: 2-[4-[(2RS)-2-hydroxy- 3-[(1-methylethyl) amino]propoxy]phenyl] acetamide.
Molecular Formula: C14H22N2O3.
Molecular Weight: 266.3.

CAS number.


7 Medicine Schedule (Poisons Standard)

S4 - Prescription Only Medicine.

Summary Table of Changes