Furosemide

What is furosemide?

Furosemide is a loop diuretic. You may often see it referred to as a “water pill”. This is because it helps your body get rid of excess fluid by increasing the amount of urine you produce[4].  

Furosemide works by acting on the kidneys and is commonly used to treat fluid retention, high blood pressure, and heart failure. It comes in tablets, oral solutions, and injectable forms, although the latter is more commonly used in hospitals[4]. 

What is furosemide used for?

Doctors or pharmacists prescribe furosemide to treat conditions where excess fluid builds up in the body, including oedema caused by conditions like congestive heart failure, liver disease, and kidney disorders. It may also be used for high blood pressure (hypertension), usually in combination with other medicines[4]. 

Who can take furosemide?

Both adults and children can take furosemide. However, the dosage and monitoring requirements vary. Furosemide should be used with caution in elderly people, as well as those with reduced kidney or liver function, low blood pressure, or diabetes. Individuals with gout or a history of electrolyte imbalances may also be unsuitable for treatment with furosemide[4]. 

It is safe during pregnancy and breastfeeding under medical supervision[4]. 

Please tell your doctor or pharmacist about any conditions you may have before starting fluoxetine, and always follow the instructions in the Patient Information Leaflet[5]. 

What is the typical dosage of furosemide?

Your dose of furosemide depends on the condition being treated – along with your response to the medicine. Between 20 to 120mg once or twice daily, adjusted based on the condition and response, is typical for adults. In children, the dose is based on weight and must be determined by a doctor or pharmacist. You should not change your dose without first consulting your healthcare provider[4]. 

How do you take furosemide?

You will usually take furosemide by mouth, with or without food. It is usually taken in the morning – helping to avoid waking up at night to urinate – when taken once per day. For twice daily dosing, the second dose should be taken around lunchtime and no later than 4pm to prevent waking in the night to urinate[4]. 

When taking furosemide, you should drink plenty of fluids unless your doctor or pharmacist tells you otherwise and follow any dietary recommendations[5]. 

Can you stop taking furosemide suddenly?

No, you should not stop taking furosemide suddenly unless advised by your medical professional. That’s because stopping the medicine abruptly can lead to a return of fluid retention and/or a sudden increase in blood pressure. Instead, your doctor or pharmacist may gradually reduce your dose if you need to stop taking it. 

What should you do if you take too much furosemide?

Taking too much furosemide can cause symptoms like severe dehydration, low blood pressure, electrolyte imbalances, and fainting or confusion. You should seek medical advice if you take too much furosemide and you feel unwell, are over 65 years or you have kidney, liver or heart failure[4]. 

What should you do if you forget a dose of furosemide?

If you forget to take furosemide, you can take the missed dose when you remember, up until 4pm. If it’s after do not take the missed dose. If it’s nearly time for your next dose, just skip the one you missed. Never take two doses at once to make up for a missed dose as this could cause serious complications[4].  

Which medicines should you avoid while taking furosemide?

Furosemide can interact with many other medicines. For that reason, you should consult with your doctor or pharmacist and use caution (or avoid) taking it with[5]: 

• Other diuretics that could increase the risk of dehydration and low electrolytes 

• NSAIDs (e.g., ibuprofen) which may reduce its effectiveness 

• Lithium which can increase the risk of lithium toxicity 

• Blood pressure medications that may increase the risk of low blood pressure 

• Certain antibiotics (e.g., aminoglycosides) which may increase the risk of hearing damage 

• Anti-arrhythmic medications (e.g., amiodarone, digoxin, sotalol) 

Some over-the-counter medicines, like soluble painkillers and heartburn remedies, contain a lot of salt that can counteract furosemide's effects.

Always inform your doctor or pharmacist about all medications and supplements you take before you start a new medicine, and follow the instructions in the Patient Information Leaflet[5].

What are the side effects of furosemide?

The most common side effects when taking furosemide include increased urination, dizziness or light-headedness when standing up, a headache, or muscle cramps[4]. 

In some cases, people experience more serious side effects for which you should seek medical help immediately, including[4]: 

• Hearing loss or ringing in the ears 

• Severe dehydration (usually occurs during a stomach bug or other illnesses leading to loss of fluid – in this case it’s best to stop taking the medication for a few days and contact your GP) 

• Allergic reactions, such as rash, itching, or swelling of the face or throat 

• Signs of a blood disorder such as unexplained bruising, high temperature, sore throat and mouth ulcers 

• Severe stomach pain, pain in the side or blood in the urine (could indicate pancreatitis or kidney inflammation) 

For any unusual or severe symptoms, or a potential allergic reaction, you should speak to your doctor right away.

If you experience any side effects, including those not listed, you are encouraged to report them via the Yellow Card Scheme or contact your doctor, pharmacist, or nurse. This information is intended as a summary for general awareness and does not replace professional medical advice.

The information provided in the side effects section is not a comprehensive list of all possible side effects associated with this medication. For a complete list of side effects, please refer to the Patient Information Leaflet (PIL) provided with your medication or consult your healthcare professional[5].

Frequently asked questions about furosemide

Is furosemide safe to take long-term? 

Yes, you can usually use furosemide in the long-term, but you’ll need regular monitoring of your kidney function and electrolyte levels to make sure everything is safe[4]. 

Can I drink alcohol while taking furosemide? 

Alcohol can worsen dizziness and dehydration. As such, it’s best to limit or avoid it when you take furosemide[4]. 

Does furosemide cause weight loss? 

Furosemide may cause temporary weight loss due to fluid removal – but it does not reduce body fat[4]. 

Can I take potassium supplements while on furosemide? 

Your doctor or pharmacist must be informed if potassium supplements are being taken as they can alter the way furosemide works. They may be recommended as furosemide can sometimes cause your potassium levels to drop[4]. 

For the official NHS guide to furosemide, visit their website.