Amiloride is known as a water tablet.

It will make you go to the toilet more often to pass urine.

Common side-effects are a mild stomach upset and a skin rash. These are not usually troublesome.

About amiloride

Type of medicine Potassium-conserving diuretic
Used for Oedema (water retention) and high blood pressure
Also called Amilamont®, Navispare® (amiloride with cyclopenthiazide), co-amilozide (amiloride with hydrochlorothiazide), co-amilofruse (amiloride with furosemide)
Available as Tablets and oral solution

Amiloride belongs to the group of medicines known as potassium-conserving diuretics. Diuretics are sometimes referred to as water tablets. It is called a potassium-conserving diuretic because, unlike some other diuretics, it does not cause your body to lose potassium. It is used to treat hypertension (high blood pressure) and oedema (water retention which is commonly caused by heart failure or liver disease).

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.  Amiloride prevents the build-up of this fluid by increasing the amount of urine your kidneys produce.

It is also used alongside other diuretics. When it is used like this, it may be prescribed as a combination tablet, such as in co-amilozide (with hydrochlorothiazide),  co-amilofruse (with furosemide), or in Navispare® (with cyclopenthiazide). Combination tablets like these help to reduce the number of tablets you need to take each day. 

Before taking amiloride

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking amiloride it is important that your doctor or pharmacist knows:

  • If you are pregnant or breast-feeding.
  • If you have kidney problems or difficulty 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, such as herbal and complementary medicines.
  • If you have ever had an allergic reaction to a medicine.

How to take amiloride

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The leaflet will give you more information about amiloride and a full list of side-effects which you may experience from taking it.
  • Take amiloride exactly as your doctor has told you. It is usual to take 1 or 2 tablets daily. Your doctor will tell you which dose is right for you. Your dose will also be on the label of the pack in order to remind you.
  • Amiloride is commonly prescribed just once daily and you can generally take the dose at a time to suit you. However, diuretics are best taken no later than mid-afternoon. This is because you will find you may need to go to the toilet a couple of times after taking them and this will disturb your sleep if you take it late in the day. If you have been prescribed more than one tablet of amiloride a day and told to take them at different times, make sure you take your last tablet no later than 6 pm.
  • You can take amiloride before or after your meals.
  • If you have been prescribed any other diuretics, take them at the same time of day as you take your amiloride tablets.
  • If you miss a dose of amiloride, take it as soon as you remember. However, if it is after 6 pm in the evening, skip the missed dose and continue taking it at the usual times the next day. Do not take two doses at the same time to make up.

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 salt balance in your bloodstream may be upset by diuretics and your doctor will 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 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 these tablets unless you are advised otherwise.
  • If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.
  • If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.

Can amiloride cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Common amiloride side-effects What can I do if I experience this?
Stomach upset, stomach ache, wind Stick to simple meals - avoid rich or spicy foods
Dry mouth Try chewing sugar-free gum or 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, tinnitus (a ringing in your ears), headache, skin rash, and feeling tired If any of these become troublesome, tell your doctor

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

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.