Experiences with
DiltiazemDiltiazem is a medicine used to treat high blood pressure.
If you have high blood pressure, taking diltiazem helps to prevent coronary heart disease, heart attacks and strokes.
It works by lowering your blood pressure and making it easier for your heart to pump blood around your body.
Diltiazem is also used to:
- prevent chest pain caused by angina
- reduce the frequency of attacks in Raynaud's phenomenon
- help heal an anal fissure
Diltiazem is available on prescription only. It comes as tablets or capsules to treat high blood pressure, angina or Raynaud's. It's also available as a cream or ointment to treat anal fissures.
Who can take diltiazem
Most adults and children aged 12 years old and over can take diltiazem.
Who may not be able to take diltiazem
Diltiazem is not suitable for some people.
To make sure it's safe for you, tell your doctor if you:
- have ever had an allergic reaction to diltiazem or any other medicine
- are pregnant, trying to get pregnant or breastfeeding
- have liver disease or kidney disease
- have heart failure or problems with your heartbeat
- have a condition that causes food to move slower than usual through your body
- have a rare inherited condition called porphyria
Dosage
Your dose of diltiazem depends on why you need the medicine and what kind your doctor has prescribed. It's important to keep taking the same brand of diltiazem once you have started.
Diltiazem tablets or capsules come as standard or slow-release. Your doctor will tell you whether you need to take them once a day or in divided doses throughout the day.
Slow-release tablets and capsules release diltiazem slower than the standard tablets and capsules.
Changes to your dose
If the dose you start on does not reduce your blood pressure enough or help to control your angina, then your doctor will gradually increase your dose.
Your doctor may also lower your dose if side effects bother you.
How to take tablets or capsules
You can take diltiazem with or without food. Swallow diltiazem tablets or capsules whole, usually with a glass of water. Do not chew or crush them.
If you find tablets or capsules difficult to swallow, speak to a pharmacist or doctor, as there may be other options.
You can take diltiazem at any time of day but try to make sure it's around the same time or times every day.
With some of the capsules and tablets you might notice what looks like a whole capsule or tablet in your poo. Do not worry, this is normal. It's just the empty outer shell of the capsule or tablet which your body does not digest.
How to use cream or ointment
For an anal fissure, you'll need to apply a 2.5cm length of diltiazem cream or ointment to the broken skin on your anus, twice a day, usually for 6 to 8 weeks. Follow the instructions on the packaging.
How long to take it for
If you're taking diltiazem for high blood pressure or angina, you'll usually take it long term, even for the rest of your life.
Talk to your doctor if you want to stop taking diltiazem. Stopping may cause your blood pressure to rise and this may increase your risk of a heart attack or stroke.
If you're using it to treat an anal fissure, you'll use the cream or ointment to heal the tear on your anus until it's no longer painful to poo. This will mean the tear has healed. This usually takes around 6 to 8 weeks.
If you stop using the cream before a fissure has fully healed, it may tear again.
If you're bothered by side effects, your doctor may be able to prescribe you a different medicine.
Keep taking diltiazem even if you feel well, as you'll still be getting the benefits of the medicine.
If you forget to take a dose and you usually take diltiazem:
- once a day – take it as soon as you remember, unless it's less than 12 hours until your next dose. In this case, skip the missed dose and take your next dose at the usual time
- twice a day – take it as soon as you remember, unless it's less than 4 hours until your next dose. In this case, skip the missed dose and take your next dose at the usual time
- 3 times a day – skip the missed dose and take your next dose at the usual time
Never have 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 a pharmacist for advice on other ways to help you remember to take your medicine.
If you take too much
Too much diltiazem can make you feel faint, dizzy or sleepy. This is because it can cause your heart to beat irregularly.
- you take more than your prescribed dose of diltiazem
Go to 111.nhs.uk or call 111
If you need to go to A&E, do not drive yourself. Get someone else to drive you or call for an ambulance.
Take the diltiazem packet or leaflet inside it, plus any remaining medicine, with you.
Common side effects
These common side effects of diltiazem happen in more than 1 in 100 people. They are usually mild and will not last long. There are things you can do to help cope with them:
Speak to a doctor or pharmacist if the advice on how to cope does not help and a side effect is still bothering you or does not go away.
Serious side effects
Serious side effects after taking diltiazem are rare and happen in less than 1 in 10,000 people.
Stop taking diltiazem and call a doctor or call 111 now if:
- you get severe pain in your stomach
- the whites of your eyes turn yellow, or your skin turns yellow although this may be less obvious on brown or black skin – this can be a sign of liver problems
- your heartbeat becomes noticeable (palpitations)
- you get chest pain that does not stop after a few minutes or is new or worse if you already have angina
Chest pain is a possible sign of a heart attack and needs to be checked out as soon as possible.
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to diltiazem.
These are not all the side effects of diltiazem. For a full list, see the leaflet inside your medicine packet.
Diltiazem and pregnancy
You can use diltiazem during pregnancy, although it's not usually recommended.
If you're taking diltiazem to treat high blood pressure, you might be switched to a different medicine if you're pregnant.
If you're taking diltiazem for angina or heart rhythm problems, you should be reviewed by a pregnancy specialist (obstetrician) and a heart specialist (cardiologist). Keep taking diltiazem until you've had your review.
If you're using diltiazem to treat anal fissures, speak to your doctor who may suggest an alternative medicine.
Diltiazem and breastfeeding
If your doctor or health visitor says your baby is healthy, you can take diltiazem while breastfeeding.
There is not much information about using diltiazem while breastfeeding, but some information shows that it passes into breast milk in tiny amounts. It's unlikely to harm your baby. However, your doctor might suggest an alternative medicine that we know more about.
If you use the cream or ointment, make sure that you've washed your hands before picking up your baby.
If you do breastfeed while taking diltiazem and you notice that your baby is not feeding as well as usual, seems unusually sleepy, looks paler than usual, or if you have any other concerns about your baby, then talk to your health visitor midwife, pharmacist or doctor as soon as possible.
Diltiazem and fertility
Diltiazem may affect male fertility. There's no evidence that diltiazem affects fertility in women.
If you're trying for a baby, or having problems getting pregnant while taking diltiazem, then speak to your doctor.
Cautions with other medicines
There are some medicines that may affect how diltiazem works.
Taking diltiazem with other medicines that lower blood pressure can sometimes lower your blood pressure too much. This may make you feel dizzy or faint. If this happens to you, tell your doctor, as your dose may need to be changed.
Tell your doctor or pharmacist before starting diltiazem if you're taking:
- antibiotics such as clarithromycin, erythromycin or rifampicin
- antifungal medicines such as itraconazole or ketoconazole
- medicines to treat HIV or HCV (hepatitis C virus)
- medicines to treat epilepsy, such as carbamazepine or phenytoin
- medicines to suppress your immune system, such as ciclosporin or tacrolimus
- more than 20mg a day of simvastatin, a medicine used to lower cholesterol
Taking diltiazem with painkillers
Paracetamol is the best painkiller to take while you're taking diltiazem. If paracetamol does not work, try ibuprofen.
Talk to your doctor if you need to take painkillers more than a few times a week.
Mixing diltiazem with herbal remedies or supplements
St John's wort is a herbal remedy taken for depression. It's thought to affect the way diltiazem works.
Talk to a pharmacist or doctor if you're thinking about taking St John's wort.
There's not enough information to say that other complementary medicines, herbal remedies and supplements are safe to take with diltiazem. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.
Related links
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