ACE inhibitors
Imidapril
An ACE inhibitor that relaxes blood vessels to lower high blood pressure.
What is Imidapril?
Imidapril is an ACE inhibitor used to lower high blood pressure. It works by blocking a hormone system that tightens blood vessels, so the vessels relax and pressure falls. A dry cough is a well-known effect, and it is not used in pregnancy.
Education and reference only. This is a plain-language guide to Imidapril — 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
Imidapril is an angiotensin-converting-enzyme (ACE) inhibitor, in the same family as ramipril and lisinopril. In the UK it is used to treat high blood pressure (hypertension). ACE inhibitors are among the first-choice medicines for blood pressure in many people, particularly those who are younger or who have diabetes.
How it works
Imidapril blocks the enzyme that converts a hormone into angiotensin II, a substance that narrows blood vessels and raises blood pressure. With less angiotensin II being made, the blood vessels relax and widen, and the body holds on to less salt and water. Both effects lower blood pressure and reduce the strain on the heart.
Company & origin
Originated / developed by: Originally developed by Tanabe Seiyaku (now Mitsubishi Tanabe Pharma); available in the UK as a branded and generic medicine..
Introduced in the 1990s as an ACE inhibitor and used in the UK for high blood pressure.
What it treats
Conditions Imidapril is used for
Practical use
How to take Imidapril
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it before food, usually at the same time each day, as food can reduce its absorption.
- Take the first dose when you can rest, as it can cause early dizziness.
- Swallow the tablet with a drink of water.
- If you become unwell with vomiting or diarrhoea, get advice, as dehydration can affect your kidneys.
- If a dose is missed, take it when you remember unless the next one is near, then skip it; never double up.
- Do not stop without advice, and tell your prescriber straight away if you think you may be pregnant.
Weighing it up
Advantages & disadvantages of Imidapril
Advantages
- Effectively lowers blood pressure and protects the kidneys in many people.
- Taken once a day and available as a low-cost medicine.
- Rarely causes the swollen ankles seen with calcium-channel blockers.
Disadvantages
- Commonly causes a dry, tickly cough that can be persistent.
- Absorption is reduced by food, so it is best taken before meals.
- Can lower kidney function and raise potassium, must be stopped in pregnancy, and can rarely cause angioedema.
Practical use
Good to know
Imidapril is usually taken before food, as food can reduce how well it is absorbed. A dry, tickly cough is a well-known effect of ACE inhibitors; if troublesome, your prescriber may switch you to an ARB. The first dose can lower blood pressure more than expected, so take it when you can rest if you feel dizzy. Kidney function and potassium are checked with blood tests. It must not be used in pregnancy. Seek urgent help for any swelling of the face, lips or throat (angioedema).
Who should not take it / use with caution
- Women who are pregnant or planning pregnancy — ACE inhibitors can harm the baby and are stopped beforehand.
- People who have had angioedema (swelling of the face or throat) on an ACE inhibitor before.
- People with narrowing of the arteries to both kidneys or severe kidney problems, without specialist advice.
Monitoring
- Blood pressure
- Kidney function and potassium around starting and after changes
Side effects
- A dry, tickly cough, which can be persistent.
- Dizziness or light-headedness, especially after the first dose or when standing up.
- Changes in kidney blood tests or a rise in potassium; rarely, swelling of the face, lips or throat (angioedema) — seek urgent help if this happens.
Key interactions
- Anti-inflammatory painkillers (NSAIDs) with a water tablet can strain the kidneys — the 'triple whammy' of an ACE inhibitor, a diuretic and an NSAID together is a known cause of kidney injury.
- Other medicines that raise potassium, including potassium-sparing water tablets and supplements.
- Other blood-pressure medicines can add to its effect and cause low pressure.
Available as: Tablets.
Answers
Imidapril: frequently asked questions
When should I take imidapril?
It is usually taken before food, because food can reduce how much is absorbed. Take it at the same time each day, following your prescriber's advice.
Why do I have a dry cough on imidapril?
A dry, tickly cough is a well-known effect of ACE inhibitors. If it is troublesome, tell your prescriber, who may switch you to an ARB that rarely causes a cough.
Can I take imidapril in pregnancy?
No. ACE inhibitors can harm a developing baby and are not used in pregnancy. Tell your prescriber straight away if you are pregnant or planning to be, so a safer option can be arranged.
What is the 'triple whammy'?
It refers to taking an ACE inhibitor, a water tablet (diuretic) and an anti-inflammatory painkiller (NSAID) together, which can strain the kidneys. Check with a pharmacist before using over-the-counter anti-inflammatories.
Why do I need blood tests on imidapril?
Blood tests check your kidney function and potassium level around starting and after any change, because ACE inhibitors can affect both.
The wider class
About ACE inhibitors
Imidapril belongs to the ace inhibitors class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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