From the Guidelines
Lasix (furosemide) can cause several serious complications, including dehydration, electrolyte imbalances, and kidney damage, and patients should be closely monitored for these adverse effects, particularly when taking high doses or having pre-existing kidney problems 1.
Common Complications
- Dehydration and electrolyte imbalances, particularly hypokalemia, hyponatremia, and hypomagnesemia, which can lead to muscle cramps, weakness, fatigue, confusion, and cardiac arrhythmias
- Kidney damage or worsening of pre-existing kidney problems, especially with high doses or prolonged use
- Increased urination, which can lead to dehydration and electrolyte imbalances if not properly managed
- Hearing loss or ringing in the ears, particularly with high intravenous doses
- Increased blood sugar levels, making diabetes management more challenging
- Allergic reactions, though rare, can occur
Monitoring and Prevention
- Patients taking Lasix should monitor for signs of dehydration, such as excessive thirst, dry mouth, dizziness, or lightheadedness
- Regular blood tests should be performed to monitor electrolytes and kidney function
- Potassium supplementation may be recommended by the healthcare provider to prevent hypokalemia
- Patients should take Lasix as prescribed and maintain adequate fluid intake unless otherwise directed
- Diuretic therapy should be discontinued if severe hyponatremia, acute kidney injury, worsening hepatic encephalopathy, or incapacitating muscle cramps develop 1
Management of Complications
- If severe hypokalemia occurs, furosemide should be stopped, and potassium supplementation should be considered
- If severe hyperkalemia occurs, anti-mineralocorticoids should be stopped
- Albumin infusion or baclofen administration may be recommended in patients with muscle cramps
- Diuretic doses should be reduced to the lowest effective dose once ascites has largely resolved 1
From the FDA Drug Label
PRECAUTIONS General Excessive diuresis may cause dehydration and blood volume reduction with circulatory collapse and possibly vascular thrombosis and embolism, particularly in elderly patients. As with any effective diuretic, electrolyte depletion may occur during Furosemide tablets therapy, especially in patients receiving higher doses and a restricted salt intake Hypokalemia may develop with Furosemide tablets, especially with brisk diuresis, inadequate oral electrolyte intake, when cirrhosis is present, or during concomitant use of corticosteroids, ACTH, licorice in large amounts, or prolonged use of laxatives. Digitalis therapy may exaggerate metabolic effects of hypokalemia, especially myocardial effects All patients receiving Furosemide tablets therapy should be observed for these signs or symptoms of fluid or electrolyte imbalance (hyponatremia, hypochloremic alkalosis, hypokalemia, hypomagnesemia or hypocalcemia): dryness of mouth, thirst, weakness, lethargy, drowsiness, restlessness, muscle pains or cramps, muscular fatigue, hypotension, oliguria, tachycardia, arrhythmia, or gastrointestinal disturbances such as nausea and vomiting. Increases in blood glucose and alterations in glucose tolerance tests (with abnormalities of the fasting and 2-hour postprandial sugar) have been observed, and rarely, precipitation of diabetes mellitus has been reported In patients with severe symptoms of urinary retention (because of bladder emptying disorders, prostatic hyperplasia, urethral narrowing), the administration of furosemide can cause acute urinary retention related to increased production and retention of urine. Thus, these patients require careful monitoring, especially during the initial stages of treatment In patients at high risk for radiocontrast nephropathy Furosemide tablets can lead to a higher incidence of deterioration in renal function after receiving radiocontrast compared to high-risk patients who received only intravenous hydration prior to receiving radiocontrast. In patients with hypoproteinemia (e.g., associated with nephrotic syndrome) the effect of Furosemide tablets may be weakened and its ototoxicity potentiated. Asymptomatic hyperuricemia can occur and gout may rarely be precipitated. Patients allergic to sulfonamides may also be allergic to Furosemide tablets. The possibility exists of exacerbation or activation of systemic lupus erythematosus As with many other drugs, patients should be observed regularly for the possible occurrence of blood dyscrasias, liver or kidney damage, or other idiosyncratic reactions.
The complications of taking Lasix (furosemide) include:
- Electrolyte depletion: hypokalemia, hypomagnesemia, hypocalcemia
- Fluid imbalance: dehydration, blood volume reduction, circulatory collapse, vascular thrombosis, and embolism
- Gastrointestinal disturbances: nausea, vomiting
- Cardiovascular effects: hypotension, tachycardia, arrhythmia
- Renal effects: deterioration in renal function, acute urinary retention
- Metabolic effects: increases in blood glucose, precipitation of diabetes mellitus
- Allergic reactions: exacerbation or activation of systemic lupus erythematosus, cross-reactivity with sulfonamides
- Idiosyncratic reactions: blood dyscrasias, liver or kidney damage 2
From the Research
Complications of Taking Lasix (Furosemide)
- Serious complications can occur if furosemide is given without caution, prior assessment of the patient's clinical status, or careful monitoring of response to therapy 3
- Potential complications include:
- Fluid and electrolyte imbalances 3, 4, 5
- Toxic effects, particularly with higher doses or in renal failure 3
- Hypokalemia (low potassium levels) 4, 6, 5
- Hyponatremia (low sodium levels) 6, 5
- Metabolic alkalosis 6
- Rhabdomyolysis (muscle breakdown) 6
- Volume depletion 5
- Furosemide-induced coma, particularly in patients with prior hepatic encephalopathy 5
- The frequency and severity of complications can be influenced by factors such as: