Cardiology - Diuretics

Diuretics are commonly referred to as ‘water tablets’.

Common diuretics are:

• Furosemide
• Bumetanide

Others include:

• Amiloride
• Metolazone
• Bendroflumethiazide

Why has my doctor given me a diuretic?

Diuretics can be used for many different reasons. In your case they have been prescribed to treat fluid congestion due to heart failure.

How do they work?

Diuretics help your body to get rid of excess fluid by encouraging your kidneys to make more urine. If they make you pass more water you may find that you have to go to the toilet more often. If this is the case you may need to plan trips out around the timings of your tablets. Diuretics help to reduce the symptoms of heart failure by removing fluid from your lungs, making breathing easier and by reducing swelling (oedema) in your legs and other parts of your body. This may result in weight loss.

How should I take my diuretic?

Always follow the instructions on the label. These medicines are usually taken in the morning. If you have been asked to take them twice a day, then take the second dose early in the afternoon. Avoid taking diuretics at night, otherwise you may wake up frequently to go to the toilet. Do not alter the amount of fluid that you normally drink while taking this medicine. It is a good idea to weigh yourself daily and keep a note of your weight to discuss with your doctor or nurse - this will help you to monitor if you are losing too much or too little fluid, so they can adjust your diuretic dose as necessary. Your doctor or heart failure nurse may ask you to adjust your diuretic dose up or down depending on your symptoms.

What should I do if I miss a dose?

Take it as soon as you remember. If it is nearly time for the next dose, do not take the one you missed. Take the next dose at the usual time. Do not double up the next dose.

What are the side effects of diuretics?

Like all medicines, diuretics can cause side effects in some people. You may experience:

• Dehydration
• Dizziness

Some diuretics can remove too much potassium (a type of salt) from your body. Your doctor or nurse can check this with a simple blood test. If this happens to you, they may change your diuretic to one that stops you losing potassium or they may give you potassium tablets. The information in this leaflet should be read together with the information provided by the manufacturer of your medication. Please read the leaflets carefully regarding instructions on storing your medication and always keep it out of the reach of children. If you have any concerns regarding your medication contact your pharmacist, doctor or heart failure nurse.