Beta-blockers

Beta-blockers (beta-adrenoceptor blocking agents) work mainly by decreasing the activity of the heart. They do this by blocking the action of hormones like adrenaline.

Beta-blockers are prescription-only medicines (POM). This means they can only be prescribed by a GP or a qualified healthcare professional.

What beta-blockers are used for

Beta-blockers may be used to treat:

• angina – chest pain caused by narrowing of the arteries supplying the heart
• heart failure – failure of the heart to pump enough blood around the body
• atrial fibrillation – irregular heartbeat
• heart attack – an emergency where the blood supply to the heart is suddenly blocked
• high blood pressure – when other medicines have been tried, or in addition to other medicines

Less commonly, beta-blockers are used to prevent migraines or treat:

• an overactive thyroid (hyperthyroidism)
• anxiety conditions
• tremor
• glaucoma – as eye drops

There are several types of beta-blocker, and each one has its own characteristics. The type prescribed for you will depend on your condition.

Who can take beta-blockers?

Before taking beta-blockers, make sure your doctor is aware of any other conditions you have. Sometimes they may not be suitable to use.

Make sure you tell your doctor if you have a history of:

• asthma or any type of lung disease
• heart disease
• kidney disease
• diabetes – particularly if you have frequent episodes of low blood sugar
• allergic reaction to any medication
• metabolic acidosis

Your GP can advise you about which medicine to use if you're pregnant or breastfeeding.

Stopping your medication

Talk to your doctor before you stop taking beta-blockers. It's important that you do not stop taking your medication suddenly.

Interactions with other medicines

Beta-blockers, including beta-blocker eye drops, may interact with and alter the effects of other medicines.

Some of the more common medicines that can interact with beta-blockers include:

• anti-arrhythmics – used to control irregular heartbeats
• antihypertensives – used to lower blood pressure
• antipsychotics – used to treat severe mental health problems
• clonidine – used to treat high blood pressure and migraine
• mefloquine – used to treat or prevent malaria

Side effects of beta-blockers

Most people taking beta-blockers have either no or very mild side effects. These usually become less troublesome with time.

Contact your GP if you're experiencing symptoms that affect your everyday life. They can discuss whether the symptoms are a result of the medication and what to do.

Don't drive if you feel dizzy, tired, or your vision is affected.

Common side effects

Symptoms often reported by people taking beta-blockers include:

• dizziness
• tiredness
• blurred vision
• cold hands and feet
• slow heartbeat
• diarrhoea
• nausea

Less common side effects

Less common side effects of beta-blockers include:

• sleep disturbance (insomnia)
• loss of sex drive (libido)
• depression
• problems getting or maintaining an erection (impotence)

The Yellow Card Scheme

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine you're taking. It's run by a medicines safety watchdog called the Medicines and Healthcare products Regulatory Agency (MHRA).

Further information on the Yellow Card Scheme.

Missed or extra doses

Most beta-blockers are taken once a day, except:

• certain beta-blockers that're used during pregnancy
• Sotalol, which is given 2 or 3 times a day

It's important not to miss any of your doses. This could make your treatment less effective.

If you forget to take a dose of your beta-blocker, you should check the patient information leaflet that comes with your medicine. It should include advice about what to do in this situation.

Never double up on a dose to make up for a missed or forgotten dose of any beta-blocker.

If you take more tablets than prescribed, contact your Pharmacist, GP or NHS 111 as soon as possible for advice.