Diuretics for Ascites (Spironolactone, Furosemide)

Diuretics (water pills): aldosterone blocker and loop diuretic

Spironolactone, furosemide (often used together)

In cirrhosis (advanced scarring of the liver), the kidneys hold on to too much salt and water, and fluid builds up in the abdomen (ascites) and sometimes the legs. Spironolactone blocks a hormone that makes the kidneys keep salt. Furosemide makes the kidneys pass more salt and water. Together they help you pass the extra fluid in your urine. Fluid goes down slowly, so the aim is a gradual loss of weight, not a sudden one.

Take them exactly as prescribed, usually in the morning so you are not up at night passing urine. Doses are set and adjusted by your doctor depending on your weight, blood tests and how well fluid is clearing. Weigh yourself at the same time each morning and write it down. Follow a low-salt diet as advised; the medicine cannot work well if you eat a lot of salt. Do not stop, and do not take extra, without talking to your doctor. Drink the amount of fluid your doctor recommends; fluid restriction is only needed in some people.

• Confusion, unusual sleepiness, or sudden change in behaviour — Dehydration or salt imbalance can trigger hepatic encephalopathy (liver-related confusion). Seek urgent medical care; go to the emergency department.

• Passing very little urine, severe dizziness or fainting, or rapid weight loss — May mean dehydration or kidney strain. Contact your doctor the same day, and do not take the next dose until you have been advised.

• Severe muscle weakness, palpitations or an irregular heartbeat — A high or low potassium level can affect the heart. Go to the emergency department.

• Fever with belly pain or tenderness, or a belly that suddenly swells and hurts — Ascitic fluid can become infected (spontaneous bacterial peritonitis), a serious emergency. Go to the emergency department now.

• Vomiting blood or black stools; severe vomiting or diarrhoea — Bleeding is an emergency; severe vomiting or diarrhoea can cause dangerous dehydration while on water pills. Seek urgent care.

Anti-inflammatory painkillers (NSAIDs such as ibuprofen or diclofenac) can stop diuretics working and can harm the kidneys in cirrhosis, so avoid them unless your doctor says otherwise. Potassium supplements, salt substitutes (which contain potassium), and some blood-pressure tablets (ACE inhibitors, ARBs) can raise potassium to unsafe levels with spironolactone. Always tell your doctor about herbal and over-the-counter products.

Blood tests for kidney function, sodium and potassium are checked before starting, within the first week or two, and then regularly. Your weight (and sometimes belly size) is tracked; doctors often aim for a gradual loss rather than a rapid one. Your doctor may lower or pause the doses if tests change.

Your doctor may pause them if you are dehydrated, have kidney problems, abnormal blood salts, confusion, or an acute illness such as vomiting or diarrhoea. Do not stop on your own unless you feel very unwell, in which case seek medical advice the same day.

Spironolactone is generally avoided in pregnancy and during breastfeeding unless a specialist decides otherwise. Tell your doctor if you are pregnant or planning pregnancy.

During Ramadan, discuss timing of doses and fluid and salt intake with your doctor beforehand, because fasting and water pills together can cause dehydration. Pickles, cheese, canned foods and salty sauces add hidden salt; check labels.

• How much salt and fluid should I have each day?

• How much weight loss per day is safe for me?

• When do I need blood tests, and who reviews them?

• What should I do on days when I have vomiting, diarrhoea or poor intake?

• Can I fast in Ramadan safely with this treatment?

This guide comes from the Saudi Gastroenterology Association (SGA) patient library, prepared by the Approved for publication by SGA; individual clinician review is ongoing. Last reviewed: 2026-04-24. It is for education and does not replace your doctor's advice.