A calcium-channel blocker
Amlodipine
A common calcium-channel blocker used for high blood pressure and angina, taken once a day.
What is Amlodipine?
Amlodipine is a long-acting calcium-channel blocker that relaxes and widens the blood vessels to lower blood pressure. It is one of the most commonly used blood-pressure medicines in the UK and is also used to relieve and prevent angina chest pain.
Education and reference only. This is a plain-language guide to Amlodipine — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Amlodipine is one of the most commonly used blood-pressure medicines in the UK. It is a long-acting calcium-channel blocker used to lower blood pressure and to prevent the chest pain of angina. It is taken as a once-daily tablet and is often a first-choice option, particularly in older people and those of African or Caribbean family origin.
How it works
Amlodipine relaxes the muscle in the walls of arteries by blocking calcium from entering those muscle cells. With the arteries more relaxed and widened, blood flows more easily, blood pressure falls and the heart receives more blood — which is why it both lowers blood pressure and eases angina.
Company & origin
Originated / developed by: Pfizer.
Amlodipine is a calcium-channel blocker discovered and developed by scientists at Pfizer in the United Kingdom in the 1980s. It received its initial FDA approval in 1992 and is marketed as Norvasc/Istin, becoming one of Pfizer's biggest-selling cardiovascular drugs.
What it treats
Conditions Amlodipine is used for
Practical use
How to take Amlodipine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Taken once a day, at roughly the same time each day.
- Can be taken with or without food, at any time of day that suits you.
- Swallow the tablet whole with a drink of water.
- If you miss a dose, skip it and take the next one as usual — do not double up.
- Mild ankle swelling is common; raising your legs can help, so mention it rather than stopping the tablet.
Weighing it up
Advantages & disadvantages of Amlodipine
Advantages
- Effective once-daily blood-pressure control with a long duration of action.
- Does not need routine blood tests for kidneys or potassium.
- Useful for both high blood pressure and angina.
- Cheap, well-established generic suitable for most people.
Disadvantages
- Commonly causes ankle and lower-leg swelling (oedema).
- Can cause flushing, headaches or palpitations, especially early on.
- Does not protect the kidneys in the way ACE inhibitors or ARBs do.
- Swelling can be bothersome enough that some people need a different medicine.
Practical use
Good to know
It is taken once daily at a consistent time and works steadily over the day. The most common effect is ankle swelling, which is not dangerous but can be bothersome; it tends to be dose-related. Unlike some heart medicines, it does not slow the heart rate.
Who should not take it / use with caution
- People with certain severe heart conditions such as unstable angina or significant narrowing of the heart's outflow (aortic stenosis), or shortly after a heart attack — assessed individually.
- Used with caution in severe liver impairment and very low blood pressure.
Monitoring
- Blood pressure
- Ankle swelling and tolerability
Side effects
- Swollen ankles or feet (common, dose-related, harmless but can be uncomfortable).
- Flushing, headache, or feeling dizzy, especially when starting.
- Palpitations or tiredness in some people.
Key interactions
- Grapefruit juice in large amounts can raise its levels.
- Care alongside other blood-pressure-lowering medicines, and with simvastatin (the statin dose may be limited).
- Certain antifungal and other medicines can raise its levels.
Available as: Tablets (several strengths); a liquid is available for those who cannot swallow tablets.
Answers
Amlodipine: frequently asked questions
Why does amlodipine make my ankles swell?
Amlodipine widens small blood vessels, which can let a little fluid collect in the lower legs, causing ankle swelling. It is not dangerous and is often dose-related; tell your prescriber if it is troublesome, as the dose or medicine can be adjusted.
Does amlodipine slow the heart rate?
No. Unlike beta-blockers or the rate-limiting calcium-channel blockers (diltiazem, verapamil), amlodipine mainly relaxes the arteries and does not slow the heart — it can occasionally cause a mild increase in heart rate.
When should I take amlodipine?
Once a day at a time you will remember; it lasts well over 24 hours so the exact time is less important than taking it consistently.
Is Istin the same as amlodipine?
Yes — amlodipine is the generic (active-ingredient) name and Istin is a brand name. Generic amlodipine contains the identical active ingredient.
Can I stop amlodipine if my blood pressure is normal?
Your blood pressure is likely normal because the medicine is working. Don't stop without advice — pressure usually rises again. Any changes should be made with your prescriber.
The wider class
About Calcium-channel blockers
Amlodipine belongs to the calcium-channel blockers class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
Browse by body system
Authoritative sources
- BNF: Amlodipine.
- electronic Medicines Compendium (SmPC): Amlodipine.
- NICE CKS: Amlodipine.
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