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  1. About metoprolol
  2. Key facts
  3. Who can and cannot take metoprolol
  4. How and when to take it
  5. Side effects
  6. How to cope with side effects
  7. Pregnancy and breastfeeding
  8. Cautions with other medicines
  9. Common questions

1. About metoprolol

Metoprolol belongs to a group of medicines called beta blockers.

It's used to:

Metoprolol can help reduce your symptoms if you have too much thyroid hormone in your body (thyrotoxicosis).

You'll usually take it together with medicines to treat an overactive thyroid.

This medicine comes as tablets and is only available on prescription. It's also given by injection, but this is usually done in hospital.

2. Key facts

  • Metoprolol slows down your heart rate and makes it easier for your heart to pump blood around your body.
  • Your very first dose of metoprolol may make you feel dizzy, so take it at bedtime. If you don't feel dizzy after that, you can take it in the morning.
  • Metoprolol is usually taken once or twice a day, but sometimes it's prescribed to be taken up to 4 times a day.
  • The main side effects of metoprolol are headaches, and feeling dizzy, sick or tired – these are usually mild and short-lived.
  • Metoprolol also goes by the brand name Lopresor. When given by injection, it may be called by the brand name Betaloc.

3. Who can and cannot take metoprolol

Metoprolol can be taken by adults over the age of 18.

It is not suitable for everyone. To make sure it's safe for you, tell your doctor before starting metoprolol if you have:

  • ever had an allergic reaction to metoprolol or any other medicine
  • low blood pressure or a slow heart rate
  • a lung disease or severe asthma
  • metabolic acidosis – when there's too much acid in your blood
  • an overactive thyroid (hyperthyroidism) – metoprolol may make it more difficult to recognise the warning signs of having too much thyroid hormone in your body (thyrotoxicosis)
  • severe blood circulation problems in your limbs (such as Raynaud's phenomenon), which may make your fingers and toes tingle or turn pale or blue
  • liver problems

4. How and when to take it

Metoprolol comes as 2 different types of tablet: standard release and slow release.

Slow release is also called sustained release (SR):

  • standard release – releases metoprolol into your body quickly (you may need to take it several times a day depending on your dose)
  • slow release – dissolves slowly so you don't have to take it as often (once a day is usually enough)

Your doctor may advise you to take your first dose before bedtime because it could make you feel dizzy.

If you do not feel dizzy after the first dose, take metoprolol in the morning.

If you have metoprolol more than once a day, try to space the doses evenly throughout the day.


Take metoprolol even if you feel well, as you will still be getting the benefits of the medicine.


How much you take depends on why you need metoprolol and the type of tablet you're taking:

  • high blood pressure: standard release – 50mg to 100mg, taken twice a day; slow release – 200mg, taken once a day
  • chest pain (angina): standard release – 50mg to 100mg, taken 2 to 3 times a day; slow release – 200mg to 400mg, taken once a day
  • an irregular heartbeat (arrhythmia) – standard release – 50mg, taken 2 to 3 times a day
  • preventing migraine: standard release – 50mg, taken 2 to 4 times a day, or 100mg , taken twice a day
  • too much thyroid hormone (thyrotoxicosis) – standard release – 50mg, taken 4 times a day

How to take it

You can take metoprolol with or without food, but it's best to do the same each day.

Swallow the tablets whole with a drink of water.

Some brands have a score line to help you break the tablet in half and make it easier to swallow.

Check the information leaflet for your brand to see if you can do this.

What if I forget to take it?

If you miss a dose, take your metoprolol as soon as you remember, unless it's nearly time for your next dose.

In this case, just leave out the missed dose and take your next dose as normal.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you often forget doses, it may help to set an alarm to remind you.

You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

What if I take too much?

Taking too much metoprolol can slow down your heart rate and make it difficult to breathe. It can also cause dizziness and trembling.

The amount of metoprolol that can lead to an overdose varies from person to person.

Urgent advice: Call your doctor or go to A&E now if:

  • you take too much metoprolol

If you need to go to hospital, do not drive yourself – get someone else to drive you or call for an ambulance.

Take the metoprolol packet or leaflet inside it, plus any remaining medicine, with you.

Find your nearest A&E

5. Side effects

Like all medicines, metoprolol can cause side effects, but many people have no side effects or only minor ones.

Side effects often improve as your body gets used to the medicine.

Common side effects

These common side effects happen in more than 1 in 100 people. They're usually mild and short-lived.

Talk to your doctor or pharmacist if the side effects bother you or last more than a few days:

  • headaches
  • feeling tired, dizzy or weak
  • cold hands or feet
  • feeling sick (nausea)
  • stomach ache

Serious side effects

It's rare, but some people have serious side effects when taking metoprolol.

Call a doctor straight away if you have:

  • shortness of breath, wheezing and tightening of the chest – these can be signs of lung problems
  • shortness of breath with a cough that gets worse when you exercise (like walking up stairs), swollen ankles or legs, chest pain, an irregular heartbeat – these are signs of heart problems
  • a fast heart rate, high temperature, trembling and confusion – these are signs of too much thyroid hormone in the blood (thyrotoxicosis)
  • yellow skin or the whites of your eyes turn yellow – these can be signs of liver problems

Serious allergic reaction

In rare cases, metoprolol may cause a serious allergic reaction (anaphylaxis).

Immediate action required: Call 999 or go to A&E now if:
  • you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking
  • your mouth, face, lips, tongue or throat start swelling

You could be having a serious allergic reaction and may need immediate treatment in hospital.

These are not all the side effects of metoprolol. For a full list, see the leaflet inside your medicine packet.


You can report any suspected side effect using the Yellow Card safety scheme.

Visit Yellow Card for further information.

6. How to cope with side effects

What to do about:

  • headaches – make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Ask your pharmacist to recommend a painkiller. Headaches usually go away after the first week of taking metoprolol. Talk to your doctor if the headaches are severe or last longer than a week.
  • feeling tired, dizzy or weak – if metoprolol makes you feel dizzy or weak, stop what you're doing, and sit or lie down until you feel better. Do not drive or use tools or machinery if you're feeling tired. Do not drink alcohol, it will make you feel worse.
  • cold hands or feet – put your hands or feet under warm running water, massage them, and wiggle your fingers and toes. Do not smoke or have drinks with caffeine in - these can make your blood vessels narrower and restrict your blood flow. Smoking also makes your skin colder. Try wearing mittens (they're warmer than gloves) and warm socks. Do not wear tight watches or bracelets.
  • feeling sick (nausea) – stick to simple meals and avoid rich or spicy food. It might help to take your metoprolol after you have eaten.
  • stomach pain – try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Putting a heat pad or covered hot water bottle on your stomach may also help. If you're in a lot of pain, speak to your pharmacist or doctor.

7. Pregnancy and breastfeeding

Metoprolol is not usually recommended in pregnancy.

If you're trying to get pregnant or are already pregnant, talk to your doctor about the benefits and possible harms of taking metoprolol.

Your doctor may recommend another medicine, such as labetalol. It's similar to metoprolol and is often prescribed for high blood pressure in pregnancy.

Metoprolol and breastfeeding

It's usually safe to take metoprolol if you're breastfeeding.

This is because only a small amount gets into breast milk, and it's not enough to cause any problems to your baby.

But speak to your doctor before taking metoprolol if your baby is premature or has kidney problems.

Non-urgent advice: Tell your doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

8. Cautions with other medicines

There are some medicines that may interfere with the way metoprolol works.

Tell your doctor if you're taking:

  • other medicines for high blood pressure – the combination with metoprolol can sometimes lower your blood pressure too much, which may make you feel dizzy or faint; tell your doctor if this keeps happening as they may change your dose
  • other medicines that can lower your blood pressure – these include some antidepressants, nitrates (for chest pain), baclofen (a muscle relaxant), tamsulosin (for an enlarged prostate), and co-careldopa and levodopa (for Parkinson's disease)
  • non-steroidal anti-inflammatory medicines (NSAIDs), such as ibuprofen – these medicines may increase your blood pressure, so it's best to keep them to a minimum
  • cough medicines that contain pseudoephedrine or xylometazoline
  • medicines for diabetes – metoprolol may make it more difficult to recognise the warning signs of low blood sugar
  • medicines for allergies – such as ephedrine, noradrenaline or adrenaline
  • medicines for asthma or chronic obstructive pulmonary disease (COPD)

Mixing metoprolol with herbal remedies or supplements

There's very little information about taking herbal remedies and supplements with metoprolol.

Important: Medicine safety

Tell your doctor or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.

9. Common questions

How does metoprolol work?

Metoprolol is a type of medicine called a beta blocker.

Like other beta blockers, metoprolol works by changing the way your body responds to some nerve impulses, especially in the heart.

It slows down your heart rate and makes it easier for your heart to pump blood around your body.

How long does it take to work?

Metoprolol starts to work after about 2 hours, but it can take up to 1 week to fully take effect.

You may not feel any different when you take metoprolol, but this doesn't mean it's not working.

It's important to keep taking your medicine.

How long will I take it for?

Treatment with metoprolol is usually long term, possibly even lifelong.

Is it safe to take for a long time?

Metoprolol is generally safe to take for a long time.

In fact, it works best when you take it for a long time.

What will happen if I stop taking it?

Stopping metoprolol suddenly can make your condition worse.

Talk to your doctor if you want to stop taking metoprolol.

If you're bothered by side effects, your doctor may be able to prescribe a different medicine for your heart problems.

If you stop taking metoprolol, it will take 1 day for it to be completely out of your body.

How does it compare with other heart medicines?

Metoprolol works as well as other beta blockers for reducing blood pressure, but is less likely to cause side effects.

That's because metoprolol works mainly on the heart. Other beta blockers, such as propranolol, work on the heart but affect other parts of the body as well.

There are lots of other medicines to lower blood pressure and treat chest pain that work in a different way from beta blockers.

They include:

Beta blockers aren't usually the first choice of treatment for high blood pressure.

The medicine your doctor prescribes depends on your age and ethnicity:

  • if you're under 55, you'll usually be offered an ACE inhibitor or an angiotensin receptor blocker
  • if you're 55 or older, or you're any age and of African Caribbean or black African origin, you'll usually be offered a calcium channel blocker

Sometimes you may have to try other blood pressure-lowering medicines if you get side effects.

Many people need to take a combination of different tablets.

Will I need to stop metoprolol before surgery?

Tell your doctor you're taking metoprolol if you're going to be put to sleep (using general anaesthetic) or have any kind of major operation.

Your doctor may advise you to stop taking metoprolol 24 hours before surgery.

This is because metoprolol can lower your blood pressure too much when it's combined with some anaesthetics.

Can I drink alcohol with it?

Drinking alcohol can increase the risk of side effects with metoprolol. It can make you feel dizzy or lightheaded.

During the first few days of taking metoprolol, or after an increase in your dose, it's best to stop drinking alcohol until you see how the medicine affects you.

It's best to stop drinking alcohol if you find metoprolol makes you feel dizzy.

Is there any food or drink I need to avoid?

You can eat and drink normally while taking metoprolol.

Eating a healthy, balanced diet can help if you have high blood pressure or a heart problem.

Will it affect my contraception?

Metoprolol will not affect your contraception.

But some types of hormonal methods of contraception, such as the combined pill and contraceptive patch, are not usually recommended for women with high blood pressure.

Talk to your doctor if you're taking a combined hormonal contraceptive.

Does metoprolol affect fertility in men or women?

There's no clear evidence to suggest that taking metoprolol will reduce fertility in either men or women.

But if you're trying for a baby or having problems getting pregnant while on metoprolol, speak to your doctor.

Will it affect my sex life?

Some people on metoprolol say their sex drive goes down or they can't get an erection.

But this isn't a common side effect and there's not enough evidence to say for sure that metoprolol causes it.

If you're having problems with your sex life, talk to your doctor.

Do I need to avoid playing sports?

You do not need to stop playing sports if you take metoprolol, but don't push yourself too much.

Regular exercise is good for you because it lowers blood pressure by keeping your heart and blood vessels in good condition.

But be aware that metoprolol is not allowed in some sports if you're competing at a high level.

Can I drive or ride a bike?

Metoprolol can make some people feel dizzy, especially when they first start taking it or after taking a bigger dose.

If this happens to you, do not drive a car, ride a bike, or use tools or machinery.

Can lifestyle changes help?

You can boost the health of your heart by making some key lifestyle changes:

  • quit smoking – smoking increases your heart rate and blood pressure. Quitting smoking brings down your blood pressure and relieves heart failure symptoms. Try to avoid secondhand smoke.
  • cut down on alcohol – drinking too much alcohol raises blood pressure over time. It makes heart failure worse, too. Try to keep to the recommended guidelines of no more than 14 units of alcohol a week. A standard glass of wine (175ml) is 2 units. A pint of lager or beer is usually 2 to 3 units of alcohol.
  • exercise – regular exercise lowers blood pressure by keeping your heart and blood vessels in good condition. It doesn't need to be too energetic - walking every day will help.
  • eat well – aim to eat a diet that includes plenty of fruit and veg, wholegrains, fat-free or low-fat dairy products, and lean proteins. It's a good idea to cut down on salt, too. Eating too much salt is the biggest cause of high blood pressure - the more salt you eat, the higher your blood pressure will be. Aim for no more than 6g of salt a day.
  • manage stress – when you're anxious or upset, your heart beats faster, you breathe more heavily and your blood pressure often goes up. Find ways to reduce stress in your life. To give your heart a rest, try napping or putting your feet up when possible. Spend time with friends and family to be social and help avoid stress.
  • vaccinations – if you have heart failure, it's recommended that you have a flu jab every year and a pneumonia vaccination (also called the pneumococcal vaccine) every 5 years. Ask your doctor about these vaccinations. You can have them free on the NHS.

Page last reviewed: 13 December 2018
Next review due: 13 December 2021