Side Effects of Bumex (Bumetanide)

Bumex, or bumetanide, is a strong diuretic and can cause side effects, with dehydration being the most serious one. This medication is commonly prescribed to treat edema (fluid retention) caused by medical problems like heart failure, kidney disease, and liver disease. It works by clearing the kidneys of excess water and sodium. Bumetanide can also be prescribed to treat high blood pressure.

Patients taking bumetanide should take note of the medication’s side effects and contact their doctor if they experience symptoms that become severe or don’t go away.

Common Side Effects

While taking bumetanide, it's common to experience the following: 

• Frequent urination
• Dizziness or lightheadedness
• Muscles cramps
• Upset stomach
• Diarrhea

If these effects are severe, don’t go away, or become worse, let your doctor know. 

Bumetanide may hinder the efficacy of other prescription medications and increase the chance of side effects. Drugs that could interact with include: 

• Ototoxic drugs (affecting hearing), including aminoglycoside antibiotics such as amikacin, Garamycin (gentamicin), or Bethkis (tobramycin)
• Medication that may be potentially nephrotoxic (damaging or destructive to the kidneys)
• Lithium and bumetanide should not be taken together because diuretics can significantly increase lithium concentration in the body and increase the risk of lithium toxicity
• Probenecid reduces the excretion of sodium in the urine (natriuresis) and the high concentration of renin in the blood (hyperreninemia) produced by bumetanide
• Antihypertensives' effects may be increased when taken with bumetanide. Dose reduction will be required if both medications are taken at the same time
• Prednisone and other corticosteroids, which can change the level of potassium in the blood
• Toxicity risk of digoxin (used to treat heart conditions) is increased with bumetanide
• Medications that contain a lot of sodium, which is found in salt, like paracetamol. Too much salt can stop bumetanide working properly

Inform your physician of the medications, vitamins, nutritional supplements, and herbal products you are taking. Your doctor will determine whether you are taking medications that may interact with bumetanide and if you can safely stop taking them. 

Serious Side Effects

Taking too much bumetanide or taking it too often may result in extreme fluid loss, electrolyte depletion (presenting as dizziness, weakness, confusion, anorexia, lethargy, cramps, and vomiting), dehydration, reduction in blood volume, and circulatory collapse. This can potentially result in vascular thrombosis (blood clots obstructing a vein) and embolism (air bubbles obstructing an artery), especially in older adults. 

Bumetanide may cause too low potassium levels in the blood (hypokalemia), especially in patients who are taking a form of digitalis like digoxin and diuretics for heart failure, hepatic cirrhosis, and ascites (fluid accumulation in the peritoneal cavity that causes abdominal swelling).

Other serious side effects that bumetanide can cause include aldosterone (a steroid hormone) excess with normal kidney function, potassium-losing nephropathy, or other conditions where hypokalemia is an added risk, particularly in people with a history of abnormal heartbeats in the lower chamber (ventricular arrhythmias).

Skin reactions—such as Steven-Johnson syndrome and toxic epidermal necrolysis—could also result from taking bumetanide.

Bumetanide can also cause the following severe adverse effects:

• Ringing in ears (tinnitus)
• Hearing loss
• Unusual bleeding or bruising
• Hives
• Difficulty breathing or shortness of breath
• Chest pain
• Renal failure

If you experience any of these symptoms, notify your doctor immediately or go to the emergency room for medical treatment.

In rare cases, bumetanide may cause an allergic reaction. Seek medical help right away if you have:

• A skin rash that may include itchy, red, swollen, blistered or peeling skin
• Wheezing
• Tightness in the chest or throat
• Trouble breathing or talking
• Swelling of the mouth, face, lips, tongue or throat

A Word From Verywell

Bumetanide may help with various serious health conditions, but it may also cause additional medical issues. No matter what you are taking bumetanide for, pay close attention to whether you are having adverse reactions to the diuretic if you are taking it regularly. To minimize side effects, let your physician know what medications, vitamins, supplements and herbal products you are taking when discussing treatment. If you experience side effects, contact your provider. Your doctor will advise you if your symptoms are common, or they may decide to prescribe a different medication to treat your condition.