Nifedipine should be used with caution in:
It should not be used in case of:
- allergy to nifedipine or to any other similar drugs (known as dihydropyridines)
- children under 18 years
- pregnancy (before week 20)
- when taking the antibiotic rifampicin
- narrowing (stenosis) of the aortic valve of the heart
- collapsing due to a heart problem (cardiogenic shock), during which you would become breathless, pale and had a cold sweat and dry mouth
- the severity or frequency of your angina rapidly worsening over a matter of hours or days
- within one month of a heart attack
- blood pressure continuing to rise despite treatment; this is a condition known as malignant hypertension
Also see list of precautions and interactions
Store protected from light in the original container at or below 25°C. Do not remove the tablets from the blister or carton except when ready to take them.
What is it used for?
- Nifedipine is used to treat high blood pressure, angina (chest pain), or a condition called Raynaud’s phenomenon, a circulation problem that causes discolouration (usually whitening) and possibly also discomfort in the fingers and toes.
- It is a calcium antagonist, sometimes known as a calcium blocker or as an antihypertensive.
- It is used to relax and expand the blood vessels. In doing this, it can reduce high blood pressure, prevent the onset of chest pain if you suffer from angina, and prevent the symptoms of Raynaud’s phenomenon.
- In general this drug is used to treat conditions due to circulation problems, high blood pressure, stable angina (chest pain or discomfort that occurs with activity or stress), and Raynaud's phenomenon.
- Benefits of being on this drug can include lower blood pressure, prevention of chest pain if you have stable angina, and preventing the onset of symptoms of Raynaud's phenomenon.
Listed below are the typical uses of nifedipine.
- High blood pressure
- Stable angina (chest pain)
- Raynaud’s phenomenon, a circulation problem that causes discolouration (often whitening) in the fingers and toes
On occasion your doctor may prescribe this medicine to treat a condition not on the above list.
HOW TO USE/TAKE
How often do I take it?
- Take this medication orally as directed by your doctor, swallow whole with a little liquid, with or without food. Do not take them with grapefruit juice.
- Different versions of nifedipine modified-release preparations may not have the same clinical effect. Do not switch to another nifedipine preparation without your doctor’s knowledge.
- Use this medication regularly in order to get the most benefit from it.
- Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
- It will only take a short time before the full benefit of this drug takes effect.
- Certain medical conditions may require different dosage instructions as directed by your doctor.
- Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.
Do I need to avoid anything?
- Avoid eating grapefruits or drinking grapefruit juice. You may feel dizzy, faint, tired or have visual disturbances that make it difficult to drive or operate machinery. This is most likely when you have just started treatment, if you change the dose, or if you take it with alcohol. Consult your doctor or pharmacist for more details.
When can I stop?
- It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.
NIFEDIPINE SIDE EFFECTS
If any of these persist or you consider them severe then inform doctor or pharmacist.
Tell your doctor immediately if you develop any of the following symptoms:
- Allergic reaction including difficulty in breathing, drop of blood pressure, fast pulse, swelling
- Fast heart beat (tachycardia)
- Shortness of breath or difficulty breathing
- Itching (possibly severe), a rash or other skin reaction
- A skin reaction of blistering, peeling of the skin, and mucosal reactions (in the nose, mouth, or genital areas)
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.
Before taking nifedipine, tell your doctor or pharmacist if you are allergic to it; or to other dihydropyridine calcium channel blockers; or if you have any other allergies.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: allergy to nifedipine or to any other similar drugs (known as dihydropyridine calcium channel blockers), during pregnancy (before week 20) or while breastfeeding, when taking the antibiotic rifampicin, if you have a narrowing (stenosis) of the aortic valve of the heart, if you may collapse due to a heart problem (cardiogenic shock) during which you would become breathless, pale and had a cold sweat and dry mouth, if the severity or frequency of your angina has rapidly worsened over a matter of hours or days, during or within one month of a heart attack, or if your blood pressure is continuing to rise despite treatment (a condition known as malignant hypertension).
Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: low blood pressure (and you were prescribed nifedipine for your angina), a heart condition where your heart cannot cope with increased strain (poor cardiac reserve), diabetes, acute porphyria, kidney dialysis, or liver disease.
Before having surgery, tell your doctor or dentist that you are taking this medication.
Does alcohol intake affect this drug?
- You may feel dizzy, faint, tired or have visual disturbances that make it difficult to drive or operate machinery. This is most likely when you have just started treatment, if you change the dose, or if you take it with alcohol.
The elderly: nifedipine should be used with caution in elderly patients, who may require a lower dose.
Pregnancy and breastfeeding - please ensure you read the detailed information below
Nifedipine is not safe to take if you are, or are planning to become, pregnant.
First trimester: avoid
Second trimester: avoid up to week 20; you may be able to use nifedipine after week 20 of your pregnancy, but only after special consideration and agreement by your doctor
Third trimester: you may be able to use nifedipine after week 20 of your pregnancy, but only after special consideration and agreement by your doctor; may inhibit labour
It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.
If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.
Only a small amount of nifedipine passes into breast milk. However, the manufacturer states that it should not be taken if you are breastfeeding.
It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.
If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.
Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.
There are medicines that are known to interact with nifedipine and your doctor may well have considered this, however if you are taking any of the following medicines please make sure your doctor or pharmacist is aware of this. Do not start, stop or change the dosage of any medicine before checking with them first.
Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:
- Other drugs to treat high blood pressure
- Cimetidine (for stomach ulcers)
- Digoxin, diltiazem, quinidine or beta-blocker (used to treat heart conditions)
- Antibiotics rifampicin, quinupristin/dalfopristin, erythromycin, ketoconazole, itraconazole or fluconazole
- Phenytoin, carbamazepine and valproic acid (used to treat epilepsy)
- Cisapride (used to treat reduced movements of the gullet (oesophagus) and stomach).
- HIV protease inhibitors indinavir, nelfinavir, ritonavir, saquinavir or amprenavir
- Antidepressant drugs fluoxetine and nefazodone
- Tacrolimus (used to prevent the rejection of transplant organs)
- Phenobarbital (used mainly to treat insomnia and anxiety)
- Grapefruit or grapefruit juice
This information does not contain all possible interactions. Therefore, before using nifedipine, tell your doctor or pharmacist of all the products you use.
Taking an overdose may cause your blood pressure to become too low and your heart beats to become irregular. Also, it may lead to nausea (feeling sick) and vomiting, a lack of energy, drowsiness, dizziness, confusion, flushing, low blood oxygen levels and, possibly, even unconsciousness. If you take more than the prescribed dose, or in the event of an overdose, seek medical advice immediately and, if possible, take your tablets or the box with you to show the doctor.
If you think you, or someone you care for, might have accidentally taken more than the recommended dose of nifedipine or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.
If you miss a dose, take it as soon as you remember and then continue taking your tablets as prescribed, waiting 12 hours before taking your next dose. Do not double the dose to catch up.