Common questions about nifedipine

Nifedipine is a type of medicine called a calcium channel blocker.

If you have high blood pressure, it works 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 muscle cells relax. This widens the blood vessels, making it easier for your heart to pump blood around your body.

In angina, nifedipine works by relaxing and widening the blood vessels which improves the blood and oxygen 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.

For Raynaud's phenomenon and chilblains, nifedipine works by relaxing and expanding blood vessels and increasing blood flow to your fingers and toes.

Nifedipine starts to work on the day you start taking it, but it may take a couple of weeks to fully take effect.

If you're taking nifedipine for high blood pressure, you may not have any symptoms. In this case, you may not feel any different when you take it. This does not mean that the medicine is not working. It's important to keep taking it. Your doctor will check to see how well it is working.

If you're taking nifedipine for angina, it will probably take a couple of weeks before you feel better. Until then, you may still get chest pain. So 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. You will need to keep taking nifedipine every day for it to work properly.

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.

Nifedipine is generally safe to take for a long time. In fact, it works best when you take it for a long time.

There are several other calcium channel blockers which work in the same way as nifedipine. They include amlodipine, felodipine, lacidipine and lercanidipine.

Verapamil and diltiazem are also calcium-channel blockers, but work in a slightly different way.

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 like ramipril and lisinopril
• angiotensin receptor blockers like candesartan
• beta blockers like bisoprolol
• diuretics like bendroflumethiazide

If you cannot take nifedipine 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.

There are other calcium channel blockers, such as felodipine, amlodipine, diltiazem and verapamil, which are used for angina.

There are also other medicines for angina which work in a different way. They include:

• beta blockers like bisoprolol
• nitrates like isosorbide mononitrate
• nicorandil

Even if nifedipine lowers your blood pressure successfully, it's best to carry on taking it. If you stop taking nifedipine, your blood pressure could go back up again.

If you need blood pressure-lowering medicines, you'll probably need to take them for the rest of your life.

Remember, by keeping your blood pressure low, you're protecting yourself against having a heart attack or stroke in the future.

There are some other possible uses of nifedipine. It's sometimes used as a treatment for:

• kidney stones
• a particular kind of unstable angina called Prinzmetal angina (or variant angina)

If you're not sure why you're taking nifedipine, or whether it's the right medicine for you, speak to your doctor or pharmacist.

No, there's no evidence that nifedipine is addictive.

Nifedipine will not affect your contraception.

However, some types of hormonal methods of contraception, like the combined pill and contraceptive patch, are not usually recommended if you have high blood pressure.

Talk to your doctor if you're taking or using combined hormonal contraceptives.

Nifedipine 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.

It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.

Talk to your doctor or pharmacist if you're unsure whether it's safe for you to drive while taking nifedipine. GOV.UK has more information on the law on drugs and driving.

Yes, you can drink alcohol while taking nifedipine but it's best not to drink too much.

Drinking alcohol may increase some of the side effects of nifedipine, such as headaches, flushing or feeling sleepy, dizzy or light-headed. If this happens to you, it's best to stop drinking alcohol while you're taking it.

Do not eat grapefruit or drink grapefruit juice. This is because grapefruit can increase the amount of nifedipine in your body, and cause side effects such as headache, flushing and feeling dizzy or faint.

Drinking alcohol can increase the blood pressure-lowering effect of nifedipine, which can make you feel dizzy or light-headed. If this happens to you, it's best to stop drinking alcohol while you're taking it.

Otherwise, you can eat and drink normally while taking nifedipine. Eating well can help if you have high blood pressure or heart failure.

You can boost the health of your heart by making some key lifestyle changes. These will also help if you have 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.
• 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 – aim to eat a diet that includes plenty of fruit and vegetables, wholegrains, fat-free or low-fat dairy products and lean proteins. It's a good idea to follow these tips for a lower salt diet 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.
• 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. 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 the flu vaccine every year and the pneumococcal vaccine as recommended by your GP. Ask your doctor about these vaccinations. You can have them free on the NHS. The coronavirus (COVID-19) vaccine is recommended for most people. Make sure you've had all the doses that you are eligible for. Talk to your doctor if you think you might be in one of the at risk groups.