About metoprolol

Metoprolol is used to treat several different problems. It works on the heart and blood vessels.

High blood pressure: it is not fully understood how metoprolol works in hypertension (high blood pressure), but it is known to slow down the activity of the heart. This then reduces high blood pressure.

Angina: by slowing down the activity of the heart, metoprolol reduces the heart's need for oxygen. This reduces how hard the heart has to work and makes angina attacks less likely to occur.

Irregular heartbeat: normally the heartbeat is regulated by special tissues which conduct electricity. Some causes of irregular heartbeat result in parts of the heart beating too quickly. Metoprolol reduces the overactivity in these conducting tissues.

To protect the heart: taking metoprolol after having a heart attack has been shown to reduce the risk of a second attack in some people.

To prevent migraine: it is not clear how metoprolol and other beta-blockers work to prevent migraine, but they are commonly used. Migraine prevention with metoprolol may be helpful for people who suffer several migraine attacks each month and also for people who find the treatments for migraine unsuitable. Although metoprolol can help prevent migraines from starting, if a migraine attack occurs, other medicines are used to treat it.

Thyroid problems: an overactive thyroid gland causes symptoms such as a fast heartbeat and trembling. Metoprolol relieves these symptoms quickly, which allows time for other antithyroid treatments to take effect, which may take several weeks.

Before taking metoprolol

Before taking metoprolol make sure your doctor or pharmacist knows:

• If you are pregnant, trying for a baby or breast-feeding.
• If you have liver or kidney problems.
• If you have low blood pressure or poor circulation.
• If you have asthma or breathing difficulties.
• If you have diabetes.
• If you have psoriasis (a skin problem).
• If you have myasthenia gravis (a condition causing muscle weakness).
• If you have heart failure (a condition where the pumping action of the heart is reduced) or heart block (a slow and irregular heartbeat).
• If you have been told you have Prinzmetal's angina (chest pain caused by spasms of the heart's blood vessels).
• If you have phaeochromocytoma (a tumour on your adrenal gland).
• If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
• If you have ever had an allergic reaction to a medicine, or if you have ever had any other severe allergic reaction.

How to take metoprolol

• Before starting this treatment, read the manufacturer's printed information leaflet from inside the pack.
• Take metoprolol exactly as your doctor has told you.
• If you have been given a sustained-release brand of metoprolol (if so, the name of your medicine will have 'SR' after it), you should swallow these tablets whole. Do not chew or crush them before you swallow, as they are made so that the metoprolol is released slowly.
• Try to take your doses of metoprolol at the same times each day to avoid missing any.
• If you do forget to take a dose, take it as soon as you remember unless it is nearly time for your next dose, in which case leave out the missed dose. Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

• Try to keep your regular appointments with your doctor. This is so your progress can be monitored.
• It is very important to follow any dietary advice that you may have been given by your doctor.
• It is recommended that you avoid drinking alcohol while you are taking metoprolol, as it may increase some of its side-effects.
• If you have diabetes, check your blood glucose levels regularly, as this medicine can affect the levels of sugar in your blood. It may also block the symptoms of low blood sugar.
• If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking metoprolol.
• Do not stop taking this medicine unless your doctor tells you to stop. Stopping treatment suddenly can cause problems in some people and your doctor will probably want you to reduce your dose gradually if this is necessary.
• If you buy any medicines, check with a pharmacist that they are safe to take with metoprolol.

Can metoprolol cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store metoprolol

• Keep all medicines out of the reach and sight of children.
• Store in a cool, dry place, away from direct heat and light.

Important information about all medicines