BMA Concise Guide to Medicine & Drugs


Brand name Tenormin

Used in the following combined preparations Beta-Adalat, Co-tenidone, Kalten, Tenif, Tenoret, Tenoretic


Drug group Beta blocker

Overdose danger rating High

Dependence rating Low

Prescription needed Yes

Available as generic Yes


Atenolol is a cardioselective beta blocker. It prevents the heart from beating too quickly and is used mainly to treat irregular heart rhythms (arrhythmias) and chest pain (angina). It may also be given following a heart attack to protect the heart from further damage. Atenolol is also used to treat hypertension (high blood pressure) but is not usually used to initiate treatment. It is less likely than non-cardioselective beta blockers to provoke breathing difficulties but, nevertheless, it is not usually given to patients with asthma. It may also slow the body’s response to low blood sugar if you are a diabetic on insulin.


Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Tablets, liquid, injection.

Frequency and timing of doses 1–2 x daily.

Adult dosage range 25–100mg daily.

Onset of effect 2–4 hours.

Duration of action 20–30 hours.

Diet advice None.

Storage Keep in original container in a cool, dry place out of the reach of children. Protect from light.

Missed dose Take as soon as you remember. If your next dose is due within 6 hours, omit the missed dose but take the next scheduled dose.

Stopping the drug Do not stop taking the drug without consulting your doctor; sudden withdrawal may lead to dangerous worsening of the underlying condition. It should be withdrawn gradually.


Seek immediate medical advice. Take emergency action if breathing difficulties, collapse, or loss of consciousness occur.


Atenolol’s adverse effects are common to most beta blockers and tend to diminish with long-term use. Lethargy, fatigue, and colds hands and feet are common. Other, rarer, adverse effects include nausea, vomiting, nightmares or vivid dreams, rash, dry eyes, and visual disturbances. Any of these effects should be reported to your doctor. If you experience fainting, palpitations, breathlessness, or wheezing, you should stop taking the drug and consult your doctor immediately.


Antihypertensive drugs Atenolol may enhance the blood-pressure-lowering effect.

Calcium channel blockers may cause low blood pressure, a slow heartbeat, and heart failure if used with atenolol.

Non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the antihypertensive effect of atenolol.

Cardiac glycosides (e.g. digoxin) may increase the heart-slowing effect of atenolol.

Antidiabetic drugs used with atenolol, may increase the risk of low blood sugar or mask its symptoms.

Decongestants used with atenolol, may increase blood pressure and heart rate.


Be sure to tell your doctor if:

· You have heart problems.

· You have a long-term kidney problem.

· You have diabetes.

· You have a lung disorder such as asthma or bronchitis.

· You have psoriasis.

· You are taking other medicines.

Pregnancy Safety in pregnancy not established. Discuss with your doctor.

Breast-feeding The drug passes into the breast milk. Discuss with your doctor.

Infants and children Not recommended.

Over 60 No special problems. Reduced dose may be necessary if there is impaired kidney function.

Driving and hazardous work Avoid such activities until you have learned how atenolol affects you because the drug can cause dizziness.

Alcohol Avoid excessive intake. Alcohol may increase the blood-pressure-lowering effects of atenolol.

Surgery and general anaesthetics Occasionally, atenolol may need to be stopped before you have a general anaesthetic, but only do this after discussion with your doctor or dentist.


No special problems expected.