Amiloride is a 'water' tablet (diuretic).
It will make you go to the toilet more often to pass urine.
Any side-effects are usually mild.
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 amiloride. 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||A potassium-sparing diuretic|
|Used for||Water retention (oedema); high blood pressure|
|Also called||Combination tablets: Co-amilozide (amiloride with hydrochlorothiazide), co-amilofruse (amiloride with furosemide), amiloride with bumetanide;|
|Available as||Tablets and oral liquid medicine|
Amiloride belongs to the group of medicines known as potassium-sparing diuretics. A diuretic is a medicine which increases the amount of urine that you pass out from your kidneys. They are often referred to as 'water' tablets. Amiloride is called a potassium-sparing diuretic because, unlike some other diuretics, it does not cause your body to lose potassium. It is used to treat high blood pressure (hypertension) and also water retention (oedema).
Oedema occurs when fluid leaks out of your blood vessels, causing swelling in the tissues of your lungs, feet or ankles. This makes you feel breathless and your legs feel puffy. It is commonly caused by heart failure or liver disease. Amiloride prevents the build-up of this fluid by increasing the amount of urine your kidneys produce.
Amiloride can be prescribed as a treatment on its own, or alongside other diuretics. When it is used with other diuretics, it can be prescribed as a combination tablet to help cut down on the number of tablets you need to take each day. Combination tablets include co-amilozide (amiloride with hydrochlorothiazide) and co-amilofruse (amiloride with furosemide).
Before taking amiloride
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 amiloride 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 if you have any difficulties passing urine.
- If you have diabetes.
- If you have been told by a doctor that you have high levels of potassium in your blood.
- If you have a problem with your adrenal glands, called Addison's disease.
- If you are taking or using 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 reaction to a medicine.
How to take amiloride
- Before you start the treatment, read the manufacturer's printed information leaflet from inside your pack. It will give you more information about amiloride and will also provide you with a full list of side-effects which you could experience from taking it.
- Take amiloride exactly as your doctor tells you to. Your doctor will ask you to take one dose, or possibly two doses, a day. The directions for taking your doses will be printed on the label of the pack to remind you about what the doctor said to you.
- Amiloride is best taken in the morning. This is because you will find you may need to go to the toilet a couple of times after taking it and this will disturb your sleep if you take it too late in the day. If you have been prescribed more than one dose a day, make sure you take your last dose no later than 6 pm.
- You can take amiloride either before or after meals.
- If you forget to take a dose of amiloride, take it when you remember unless it is late in the day. If it is after 6 pm in the evening, leave out the missed dose completely and take your next dose when it is due on the following day. Do not take two doses at the same time 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 doctor can check on your progress. The balance of salts in your blood may be upset by amiloride so your doctor may want you to have a blood test from time to time to check for this.
- Diuretics help you to lose water, so you can breathe and move more easily. If, however, you lose too much fluid, you may become lacking in fluid in the body (dehydrated). This will make you feel thirsty and make your skin look and feel dry. Let your doctor know if this happens, as your dose may need to be adjusted.
- Because amiloride is a potassium-conserving diuretic, you should try to avoid things with a high potassium content, such as 'salt substitutes'. This is so the level of potassium in your body does not become too high.
- Treatment with diuretics is usually long-term, so continue to take amiloride unless your doctor advises you otherwise.
- If you buy any medicines 'over the counter', please check with a pharmacist that they are suitable for you to take alongside your prescribed medicines.
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 amiloride 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 ones associated with amiloride. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Amiloride side-effects||What can I do if I experience this?|
|Stomach upset, stomach ache||Stick to simple meals - avoid rich or spicy foods|
|Dry mouth||Try chewing sugar-free gum or sucking sugar-free sweets|
|Feeling dizzy or faint especially when getting up||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 minutes before you stand|
|Muscle cramps, aches or pains, eyesight problems, a ringing in your ears (tinnitus), headache, skin rash, and feeling tired||If any of these become troublesome, tell your doctor|
|Changes to the results of some blood tests||Your doctor may check for these from time to time|
If you experience any other symptoms which you think may be due to the medicine, please speak with your doctor or pharmacist for further advice.
How to store amiloride
- 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.
If you are due to have an operation or any dental treatment, please tell the person carrying out the treatment which medicines you are taking.
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, Amiloride 5 mg Tablets; Wockhardt UK Ltd, The electronic Medicines Compendium. Dated July 2015.
Manufacturer's PIL, Amiloride 5 mg/5 ml Oral Solution; Essential Pharma Ltd. The electronic Medicines Compendium. Dated November 2021.
British National Formulary, 82nd Edition (Sep 2021); British Medical Association and Royal Pharmaceutical Society of Great Britain, London.