The first dose of enalapril can make you feel dizzy. It is best taken at bedtime.
Enalapril is generally well tolerated but if you develop a troublesome cough, you must let your doctor know.Some painkillers and indigestion remedies can interfere with enalapril. Ask your pharmacist for advice before you buy any medicines 'over the counter'.
Clinical author's note: Michael Stewart 15/11/2018: Following an MHRA update, new advice has been added to this leaflet for people also taking the blood pressure medicine hydrochlorothiazide. Hydrochlorothiazide is only available in the UK in combination with other blood pressure medicines such as enalapril. It may be available on its own in other countries. For more information see 'Getting the most from your treatment' below or view the MHRA Alert.
|Type of medicine||An angiotensin-converting enzyme (ACE) inhibitor|
|Used for||High blood pressure; heart failure|
|Also called||Innovace®; Innozide® (contains enalapril with hydrochlorothiazide)|
Enalapril belongs to a class of medicines called angiotensin-converting enzyme (ACE) inhibitors. You may have been prescribed it to reduce high blood pressure (hypertension), or to prevent (or treat) heart failure. Heart failure is a condition where your heart does not work as well as it should.
ACE inhibitors like enalapril prevent your body from creating a hormone known as angiotensin II. They do this by blocking (inhibiting) a chemical called angiotensin-converting enzyme. This widens your blood vessels and helps to reduce the amount of water put back into your blood by your kidneys. These actions help to decrease blood pressure. Although people with high blood pressure often do not feel unwell, if left untreated, high blood pressure can harm the heart and damage blood vessels, leading to a heart attack or stroke. Enalapril can be used on its own or alongside other medicines which reduce blood pressure. A combination brand called Innozide® (which contains enalapril with another medicine called hydrochlorothiazide) can help to reduce the total number of tablets people with high blood pressure need to take each day.
In heart failure, there can be too much circulating fluid in your blood vessels because your heart is not working as efficiently as it once did. Enalapril helps to reduce this. It also appears to have a protective effect on the heart and slows the progression of the heart failure.
Before taking enalapril
Some medicines are not suitable for people with certain conditions, and sometimes a medicine can only be used if extra care is taken. For these reasons, before you start taking enalapril it is important that your doctor knows:
- If you are pregnant or breastfeeding.
- If you have any problems with the way your kidneys work, or any problems with the way your liver works.
- If you are lacking in fluid in the body (dehydrated) - for example, if you have had diarrhoea or sickness very recently.
- If you have been told you have a build-up of fatty deposits on the walls of your arteries, a condition called atherosclerosis.
- If you have a particular type of poor circulation called peripheral arterial disease.
- If you have collagen vascular disease - this includes conditions such as systemic lupus erythematosus (SLE) and scleroderma.
- If you have been told you have heart muscle disease (cardiomyopathy), or narrowing of the main blood vessel from your heart (aortic stenosis).
- If you have ever had a reaction where your face, tongue or throat swells (angio-oedema).
- If you are having desensitisation treatment to protect against bee and wasp stings.
- If you are having dialysis treatment, or treatment to remove cholesterol from your blood by a machine (LDL apheresis).
- If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
- If you have ever had an allergic or unusual reaction to any other ACE inhibitor (such as captopril, ramipril or perindopril), or to any other medicine.
How to take enalapril
- Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about enalapril and will provide you with a full list of side-effects which you could experience from taking it.
- Take the tablets exactly as your doctor tells you to.
- If you are being treated for high blood pressure: enalapril is taken once a day. You will be advised to take your very first dose at bedtime. This is because you can feel quite dizzy when you first start taking it. After the first dose, you can generally take enalapril at a time of day you find easy to remember. For most people this will be in the morning.
- If you are being treated for heart failure: your doctor will give you a small once-daily dose to begin with, and then your dose will be increased gradually over a few weeks. Once the dose has been increased, enalapril is commonly taken as two doses a day, one taken in the morning and the other in the evening. Increasing your dose slowly like this helps to avoid unwanted side-effects, such as dizziness.
- Try to take your doses at the same time(s) of day each day as this will help you to remember to take your doses regularly. You can take enalapril tablets either with or without food. It is best to swallow the tablet with a drink of water.
- There are several strengths of enalapril tablet. Your doctor will prescribe the strength which is suitable for your condition. Each time you collect a new supply, check to make sure the tablets are the strength that you are expecting.
- If you forget to take a dose at your usual time, take it as soon as you remember (unless it is nearly time for your next dose, in which case do not take the forgotten dose but take the next dose when it is due). Do not take two doses together to make up for a missed dose.
Getting the most from your treatment
- Try to keep your regular appointments with your doctor. This is so your progress can be monitored. Your doctor will want you to have some blood tests from time to time to check that your kidneys are working well.
- It is very important that you follow any dietary and lifestyle advice that you have been given by your doctor. This can include advice about eating a healthy diet, not smoking, and taking regular exercise.
- If you buy any medicines, check with a pharmacist that they are suitable to take with enalapril. This is because some medicines (such as anti-inflammatory painkillers and indigestion remedies) can interfere with your treatment.
- It is likely that your doctor will advise that you do not use salt substitutes while you are taking enalapril. These products have a high content of potassium which could be harmful for you.
- If you drink alcohol, ask your doctor for advice about drinking alcohol while you are on enalapril. Alcoholic drinks can make you feel light-headed or dizzy, and they may not be advisable for you.
- If you have diabetes you may need to check your blood glucose more frequently, as the tablets can lower the levels of sugar in your blood. Your doctor will advise you about this.
- If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking enalapril. This is because some anaesthetics could cause your blood pressure to drop too low.
- Treatment with enalapril is often long-term unless you experience an adverse effect. Continue to take the tablets unless you are advised otherwise.
If you are also taking hydrochlorothiazide in combination with this medicine
- Studies have suggested that taking higher doses of hydrochlorothiazide for long periods of time may increase the risk of certain skin cancers.
- Tell your doctor if you have ever been treated for skin cancer before.
- Tell your doctor about any new or changed moles or worrying marks on your skin.
- Use a sunscreen in strong sunlight. Do not use sunbeds.
Can enalapril cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the more common ones associated with enalapril. The best place to find a full list of the side-effects which can be associated with your medicine, is from the manufacturer's printed information leaflet supplied with the medicine. Alternatively, you can find an example of a manufacturer's information leaflet in the reference section below. Speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Very common enalapril side-effects (these affect more than 1 in 10 people)||What can I do if I experience this?|
|Dry irritating cough||If this continues, speak with your doctor, as a different type of medicine may be more suitable for you|
|Feeling dizzy or weak||Getting up more slowly should help. If you begin to feel dizzy, lie down so that you do not faint, then sit for a few moments before standing. If this continues beyond the first few days, speak with your doctor. Do not drive and do not use tools or machines while you feel dizzy|
|Blurred eyesight||Do not drive and do not use tools or machines while affected|
|Feeling sick (nausea)||Stick to simple foods - avoid fatty or spicy meals|
|Common enalapril side-effects (these affect less than 1 in 10 people)||What can I do if I experience this?|
|Headache||Drink plenty of water and ask a pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know|
|Tummy (abdominal) pain, diarrhoea||Stick to simple foods - avoid fatty or spicy meals|
|Low mood, feeling short of breath, taste disturbances, feeling faint, skin rash||If any of these become troublesome, speak with your doctor|
|Changes to the results of some blood tests||Your doctor will check for this|
Important: if you experience any of the following potentially serious symptoms, stop taking enalapril and contact your doctor for advice straightaway:
- Any difficulty breathing, or swelling of your face, mouth, tongue or throat. These are signs of an allergic reaction.
- Any yellowing of your skin or the whites of your eyes. These may be signs of a liver problem called jaundice, which is a rare side-effect.
- A severe skin rash.
If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.
How to store enalapril
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
Important information about all medicines
Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
Further reading and references
Manufacturer's PIL, Innovace® tablets; Merck Sharp & Dohme Limited, The electronic Medicines Compendium. Dated June 2019.
British National Formulary, 78th Edition (Sep 2019); British Medical Association and Royal Pharmaceutical Society of Great Britain, London.