1. About verapamil
It's also used to treat high blood pressure (hypertension).
If you have high blood pressure, taking verapamil helps to prevent:
A specialist can also prescribe verapamil for cluster headaches. It can reduce the number of headaches you get.
Verapamil is only available on prescription.
It comes as tablets or as a liquid you swallow. It's also given as an injection, but this is usually only done in hospital.
2. Key facts
- Verapamil lowers your blood pressure and makes it easier for your heart to pump blood around your body.
- Verapamil starts to work on the day you start taking it, but it may be 1 or 2 weeks before it reaches its full effect.
- The most common side effect of verapamil is constipation.
- Do not eat grapefruit or drink grapefruit juice while you’re taking verapamil. It can make side effects worse.
- It's important to keep taking verapamil. Stopping may cause your blood pressure to rise and this may increase your risk of a heart attack or stroke.
3. Who can and cannot take verapamil
Most adults can take verapamil. It can also be given to children aged 1 year and over.
Verapamil is not suitable for some people. To make sure verapamil is safe for you, tell your doctor if you:
- have ever had an allergic reaction to verapamil or any other medicine
- have liver problems
- have low blood pressure (hypotension)
- have any other heart problems, including heart failure, or a very slow or irregular heart rate
- have a heart condition called Wolff-Parkinson-White syndrome
- are trying to get pregnant, are already pregnant or breastfeeding
4. How and when to take verapamil
Take verapamil exactly as your doctor has told you and follow the instructions that come with your medicine. If you're not sure, ask a pharmacist or your doctor.
Verapamil comes as standard tablets, slow-release (long-acting) tablets, and a liquid (oral solution).
Slow-release tablets release the medicine gradually into your body. This means you do not need to take them as often.
The dose of verapamil depends on why you're taking it.
If you have liver disease, your doctor may prescribe you a low dose and will monitor you more closely.
If a doctor has prescribed verapamil for your child, the dose will usually be lower than adults. It will depend on how old your child is. Children will usually be given standard tablets or liquid.
Dosage for high blood pressure
Standard tablets or liquid – you'll usually start on a dose of 120mg, taken twice a day. Your doctor may increase your dose to a maximum of 480mg a day, split into divided doses.
Slow-release tablets – you'll usually start on a dose of 240mg, taken once a day. Your doctor may increase it to 480mg a day. If your dose is higher than 240mg daily, it can be split into 2 doses and taken morning and evening.
Liquid verapamil contains 40mg in each 5ml spoonful.
Dosage for angina
Standard tablets or liquid – the usual dose is 80mg or 120mg, taken 3 times a day, although some people may find that taking verapamil twice a day is enough to control their symptoms.
Long-acting tablets – the usual dose is 240mg, taken twice a day. Your doctor might reduce this dose to 240mg, taken once a day.
Dosage for irregular heart rhythm
Standard tablets or liquid – the usual dose is between 40mg and 120mg, taken 3 times a day.
Dosage after a heart attack
Slow-release tablets – the usual dose is 360mg a day, split into 2 or 3 doses throughout the day. This can be taken as 240mg in the morning and 120mg in the evening, or as 120mg taken 3 times a day.
You'll usually wait at least 1 week after a heart attack before starting verapamil.
Will my dose go up or down?
If the dose you start on does not work well enough (your blood pressure does not lower enough, or your angina is not controlled), then your doctor will gradually increase your dose.
Your doctor may also lower your dose if your blood pressure is controlled or the side effects bother you.
How to take verapamil
Swallow your tablets whole with a drink of water. Do not chew or crush them, as it's important that they go into your stomach before they dissolve.
You can take verapamil at any time of day. It may help you to remember if it's the same time each day.
If you're taking verapamil as a liquid, it will come with a plastic syringe or spoon to help you take the right amount. If you do not get one, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not give you the right amount.
You can take verapamil with or without food.
It's important not to eat grapefruit or drink grapefruit juice while you're taking this medicine. Grapefruit can increase the amount of verapamil in your body and make side effects worse.
What if I forget to take it?
If you forget to take your medicine, take it as soon as you remember unless it's nearly time for your next dose. In this case, leave out the missed dose and take the next one at the usual time.
Do not take 2 doses at the same time to make up for a missed dose. Never take an extra dose to make up for a forgotten one.
If you forget doses often, 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 verapamil can cause your blood pressure to go too low. It can also make you feel faint, dizzy or sleepy because it can cause your heart to beat irregularly.
If you need to go to the hospital, do not drive yourself. Get someone else to drive you or call for an ambulance.
Take your verapamil packet or the leaflet inside it plus any remaining medicine with you.
5. Side effects
Like all medicines, verapamil can cause side effects in some people, but many people have no side effects or only minor ones.
Side effects often get better as your body gets used to the medicine.
Common side effects
Common side effects happen in more than 1 in 100 people. They are usually mild and do not last long.
Talk to your doctor or pharmacist if these side effects bother you or do not go away:
- feeling or being sick (nausea or vomiting)
- flushing of the face and neck
- feeling dizzy or tired
- swollen hands, ankles or feet
Serious side effects
Serious side effects are rare and happen in less than 1 in 10,000 people.
Stop taking verapamil and tell your doctor straight away if:
- the whites of your eyes or your skin turn yellow, although this may be less obvious on brown or black skin, or you have dark pee – these can be signs of liver problems
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to verapamil.
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 verapamil. For a full list see the leaflet inside your medicines packet.
You can report any suspected side effect using the Yellow Card safety scheme.
6. How to cope with side effects of verapamil
What to do about:
- constipation – eat more high-fibre foods such as fresh fruit, vegetables and cereals, and drink plenty of water. If you can, it may also help to increase your level of exercise. If this does not help, talk to your pharmacist or doctor about treatments for constipation.
- feeling or being sick – stick to simple meals and do not eat rich or spicy food. It might help to take your verapamil after a meal or snack. If you are being sick, try to take small, frequent sips of water to avoid dehydration.
- flushing – try cutting down on coffee, tea and alcohol. It might help to keep the room cool and use a fan. You could also spray your face with cool water or sip cold or iced drinks. The flushing should go away after a few days. If it does not go away or it's causing you problems, contact your doctor.
- headaches – make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Paracetamol is safe to take with verapamil. Headaches should usually go away after the first week of taking verapamil. Talk to your doctor if they last longer than a week or are severe.
- feeling dizzy or tired – if verapamil makes you feel dizzy, stop what you're doing and sit or lie down until you feel better. If it makes you feel tired make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Do not drive, ride a bike or operate tools or machinery until you feel OK.
- swollen hands, ankles or feet – raise your legs or elevate your arms on a cushion when you're sitting down. This will get better after a few days as your body gets used to the medicine. If it does not, or it gets worse, speak to your doctor.
7. Pregnancy and breastfeeding
Verapamil and pregnancy
Verapamil can be taken during pregnancy, although it is not commonly used.
If you need to take verapamil to treat high blood pressure you will usually be switched to a different medicine.
If you're taking verapamil for angina or heart rhythm problems then you will be reviewed in a maternity clinic with a pregnancy specialist (obstetrician) and a heart specialist (cardiologist). Keep taking verapamil until you have been reviewed.
Verapamil and breastfeeding
If your doctor, health visitor or midwife says your baby is healthy, it is OK to breastfeed while taking verapamil.
Verapamil passes into breast milk in small amounts, and it's unlikely to cause any side effects in your baby.
It's important to keep taking verapamil to keep you well. Breastfeeding will also benefit both you and your baby.
If you notice that your baby is not feeding as well as usual, or seems unusually sleepy, or if you have any other concerns about your baby, talk to your health visitor or midwife as soon as possible.
Non-urgent advice: Tell your doctor if you're:
- trying to get pregnant
For more information about how verapamil and other calcium channel blockers can affect you in pregnancy, read this leaflet on the Best Use of Medicines in Pregnancy (BUMPs) website.
8. Cautions with other medicines
Some medicines can affect the way verapamil works.
Taking verapamil with other medicines that lower your blood pressure can sometimes lower it too much. This may make you feel dizzy or faint. If this happens to you, tell your doctor, as they may need to change your dose.
Tell your doctor if you are taking any of these medicines before starting verapamil:
- antibiotics, such as clarithromycin, erythromycin or rifampicin
- antifungal medicines, such as itraconazole or ketoconazole
- ivabradine, a medicine for angina and heart failure
- darunavir or ritonavir, medicines that treat HIV or hepatitis C
- epilepsy medicines like carbamazepine or phenytoin
- medicines that suppress your immune system, such as cyclosporin or tacrolimus
- more than 20mg a day of simvastatin (a medicine used to lower cholesterol)
Mixing verapamil with herbal remedies and supplements
St John's wort (a herbal remedy for depression) can affect the way verapamil works.
Talk to a pharmacist or doctor before taking St John's wort.
Important: Medicine safety
Tell your doctor or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.
9. Common questions about verapamil
How does verapamil work?
Verapamil is a type of medicine called a calcium channel blocker.
If you have high blood pressure, these medicines work by blocking calcium going into muscles in the heart and blood vessels.
Muscles need calcium to contract, so when you block the calcium, it makes the muscles relax. This lowers your blood pressure and makes it easier for your heart to pump blood around your body.
In angina, verapamil works by improving the blood supply to your heart. Angina is chest pain that comes on when not enough blood gets to the muscles of the heart.
It usually happens because the arteries to the heart have become hardened and narrowed. Verapamil widens the arteries so more oxygen gets to the heart which prevents chest pain.
For an irregular heart rhythm, verapamil works by slowing down your heart rate as well as improving the blood supply to your heart.
How long does it take to work?
Verapamil starts to work on the day you start taking it, but it may take a couple of weeks to reach full effect.
If you're taking verapamil for high blood pressure or an irregular heart rhythm you may not have had any symptoms before.
If this is the case, you may not feel any different when you take it. However the medicine is still working and it's important to keep taking it. Your doctor will check to see how well it is working.
If you're taking it for angina, you may still get some chest pain until the verapamil starts working fully. Make sure you have your medicine (spray or tablets) for treating angina attacks with you all the time and use it if you need to.
Talk to your doctor if your chest pain does not get any better after a couple of weeks. If it gets worse, tell your doctor straight away.
How long will I take it for?
Usually, treatment with verapamil is long term, even for the rest of your life.
Can I stop taking verapamil?
Talk to your doctor if you want to stop taking verapamil.
Stopping verapamil may cause your blood pressure to rise and this may increase your risk of a heart attack or stroke.
If you're bothered by side effects, talk to your doctor. They may be able to prescribe a different medicine for you.
Are there other medicines for high blood pressure?
There are several other calcium channel blockers that can be used for high blood pressure such as:
There are also lots of other types of medicines to lower your blood pressure. They work in a different way to calcium channel blockers and include:
- ACE inhibitors such as ramipril and lisinopril
- angiotensin receptor blockers such as candesartan
- beta blockers like bisoprolol
- diuretics such as bendroflumethiazide
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.
If you cannot take verapamil or other calcium channel blockers because of side effects, you may be able to switch to another medicine.
Your doctor will advise which one is best for you depending on your age, ethnicity and medical history. Many people need to take a combination of medicines for high blood pressure.
Are there other medicines for angina?
There are other calcium channel blockers that can help with angina symptoms, such as:
There are also other medicines used to prevent angina attacks. They include:
- beta blockers such as bisoprolol
- nitrates such as isosorbide mononitrate
- medicines such as ranolazine, nicorandil or ivabradine
These medicines work in different ways so it's difficult to say whether one is better than the other.
If verapamil does not work for you, you may be able to switch to another medicine. Your doctor will be able to decide which medicine is best for you. Some people may need to take a combination of medicines to control their angina symptoms.
Are there other medicines for an irregular heart rhythm?
Diltiazem is another calcium channel blocker that can be used for irregular heart rhythms (arrhythmias).
Some other medicines which are used for arrhythmias and help control heart rate include:
These medicines all work differently and side effects can vary. Your doctor will be able to recommend the best medicine for your particular type of arrhythmia.
You may need to try a few different medicines before you find a combination that controls your symptoms but does not cause side effects.
Will it affect my contraception?
Will it affect my fertility?
There's no clear evidence to suggest that taking verapamil will reduce fertility in either men or women. Talk to your doctor if you're having problems getting pregnant while taking verapamil.
Speak to your doctor if you're trying for a baby as they may want to review your treatment.
Can I drink alcohol with it?
Yes, you can usually drink alcohol with verapamil. However, it's best to not drink alcohol for the first few days when you start taking verapamil or if your doctor increases your dose. Wait until you know how the medicine affects you.
This is because drinking alcohol can increase the effects of verapamil. It can make your blood pressure too low and you may feel dizzy or lightheaded.
Is there any food or drink I need to avoid?
Do not eat grapefruit or drink grapefruit juice while taking verapamil. This is because grapefruit can make the side effects of verapamil worse.
Otherwise, you can eat and drink normally while taking verapamil.
Eating a healthy balanced diet can help if you have high blood pressure.
Can I drive or ride a bike?
Verapamil can make some people feel dizzy. If this happens to you, do not drive a car, ride a bike, or use tools or machinery until you feel better.
Can lifestyle changes help high blood pressure or angina?
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 does not need to be too energetic – walking every day will help.
Eat well – try to include plenty of fruit and veg, wholegrains, fat-free or low-fat dairy products and lean proteins in your diet. It's a good idea to cut down on salt too.
Reduce your salt intake – 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.
Deal with stress – when you're anxious or upset, your heart beats faster, you breathe more heavily and your blood pressure often goes up. This can make heart failure worse too. Find ways to reduce stress in your life. To give your heart a rest, try napping or putting your feet up when possible.
Vaccinations – if you have heart failure, it's recommended that you have a flu vaccine every year and a pneumococcal vaccine every 5 years. Ask your doctor about these vaccinations. You can have them free on the NHS.