Furosemide

What furosemide is for

Furosemide is mainly used to treat a build-up of fluid in the body (oedema), which often affects your hands, arms, feet or legs.

It's a type of medicine called a diuretic, sometimes called water tablets because they make you pee more. This helps to get rid of excess fluid from your body.

You might be offered furosemide if you have oedema because of a condition that affects your heart, kidneys or liver, such as:

• heart failure
• chronic kidney disease
• severe liver damage (cirrhosis)

Furosemide is also sometimes used to help treat high blood pressure (hypertension).

How to take furosemide

Furosemide usually comes as tablets or liquid that you swallow.

How much you need to take and for how long depends on why you're taking it.

Your doctor may prescribe a low dose to start with and increase it after a week or more. This reduces the chances of side effects.

You usually take it once a day at first, but if your doctor decides to increase your dose then you may need to take it twice a day.

Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.

When taking furosemide:

• try to take it at the same time each day – ideally every morning if you take it once a day, or at the same time every morning and late afternoon if you take it twice a day
• swallow tablets and capsules with water
• you can take it with or without food

You may need to take furosemide for a long time if your swelling is because of a long-term condition like heart failure. If you take it for a long time, you'll be offered regular blood tests to check your health.

Taking furosemide can make you feel like you need to pee more urgently and frequently, so it may be useful to plan for this after taking it.

If you get ill with vomiting, diarrhoea or a high temperature (fever) when taking furosemide, there's a risk you'll get dehydrated.

Talk to a pharmacist or doctor for advice or follow the advice they've already given you.

If you miss a dose of furosemide

If you forget to take a dose of furosemide, take it as soon as you remember, unless it's nearly time for your next dose.

If it's nearly time for your next dose, skip the dose you missed and take your next dose at the usual time.

Do not take 2 doses to make up for a missed dose.

If you take too much furosemide

Taking an extra dose of furosemide can be dangerous.

Side effects of furosemide

Like all medicines, furosemide can cause side effects, but not everyone gets them.

Common side effects

Common side effects of furosemide can include:

• peeing more than usual
• feeling thirsty, with a dry mouth and lips (these can be signs of dehydration)
• dizziness
• headaches
• muscle twitches

If you feel dizzy or drowsy after taking furosemide, do not drive, ride a bike or use machinery until you no longer have these symptoms.

Serious side effects

Furosemide can sometimes cause serious side effects, although most of them are rare.

Possible serious side effects of furosemide can include:

• an allergic reaction (anaphylaxis) - causing symptoms such as a swollen throat or tongue, a raised itchy rash and difficulty breathing
• blistering skin around the mouth, eyes, nose or genitals, with flu-like symptoms (Stevens-Johnson syndrome)
• pain in your lower back or side, feeling sick, a high temperature, and having problems with peeing or having blood in your pee – these could be signs of kidney problems
• becoming very dehydrated – causing symptoms like peeing less than usual, having dark yellow or brown coloured pee, feeling dizzy or lightheaded, feeling tired, sunken eyes and confusion

More about side effects

These are not all the side effects of furosemide.

For a full list, see the leaflet that came with your medicine or search for your medicine leaflet on the electronic medicines compendium website.

You can report any side effects you get on the Yellow Card website.

Who can and cannot take furosemide

Most adults can take furosemide. Sometimes it’s suitable for children.

But furosemide is not suitable for everyone. For example, it may not be suitable if:

• you've had an allergic reaction or serious side effect from taking furosemide or another type of diuretic
• you have kidney or liver problems
• you have diabetes or Addison's disease
• you have or have had gout
• you have low blood pressure

Before taking furosemide, tell your doctor if you have any medical conditions.

Breastfeeding and furosemide

Tell your doctor if you're breastfeeding. Furosemide is not usually used while breastfeeding. Your doctor may offer a different treatment while you're breastfeeding.

Pregnancy and furosemide

Tell your doctor if you're pregnant or trying to get pregnant. Furosemide is not usually used during pregnancy.

Find out more about taking diuretic medicines during pregnancy on the Bumps (Best Use of Medicines in Pregnancy) website.

Taking furosemide with other medicines, food and drink

There are some medicines and supplements that may not mix well with furosemide.

This includes:

• other medicines used to treat high blood pressure, including aliskerin, beta blockers and ACE inhibitors like lisinopril
• medicines used to treat heart rhythm problems, including digoxin, amiodarone, flecainide and sotalol
• medicines or supplements that increase your potassium levels
• some non-steroidal anti-inflammatory drugs (NSAIDs)
• medicines used to treat constipation (laxatives)
• fluconzanole (an antifungal commonly used to treat thrush)
• antidepressants, such as amitriptyline and sertraline
• antipsychotics, such as risperidone
• lithium (used to treat some mental health problems)

This is not the full list of medicines that may not mix well with. Before taking it, tell your doctor if you’re taking any other medicines, herbal remedies, vitamins or supplements.

Food, drink and alcohol with furosemide

You can eat as normal while taking furosemide, but check with your doctor how much fluid you can drink while you’re taking it.

It’s important not to get dehydrated while taking furosemide, but how much you drink will depend on why you’re taking it.

It’s best not to drink alcohol because it can cause side effects like dizziness, feeling light-headed and dehydration.