What Diuretics Are Used for Rhabdomyolysis? A Clinical Review

October 14, 2025 •

3 min read

Rhabdomyolysis accounts for an estimated 26,000 hospitalizations annually in the United States. While aggressive intravenous (IV) fluid resuscitation is the primary treatment, the question of what diuretics are used for rhabdomyolysis remains a topic of clinical debate and careful consideration.

Quick Summary

The cornerstone of rhabdomyolysis management is aggressive IV fluid therapy to prevent acute kidney injury. The use of diuretics like mannitol and furosemide is controversial and not routinely recommended, reserved for specific scenarios like inadequate urine output despite fluid resuscitation.

Key Points

IV Fluids are Primary: Aggressive intravenous fluid resuscitation is the cornerstone of rhabdomyolysis treatment, not diuretics.
Diuretic Use is Controversial: Routine use of diuretics like mannitol or furosemide to prevent kidney injury is not recommended by major guidelines due to a lack of evidence.
Specific Indications Only: Diuretics are reserved for specific scenarios, such as inadequate urine output despite sufficient fluid administration or to manage volume overload.
Mannitol's Role: Mannitol, an osmotic diuretic, is sometimes considered for its ability to increase urine flow and potential antioxidant effects, but its benefit over fluids alone is unproven.
Furosemide's Risks: Loop diuretics like furosemide can acidify urine, which may worsen myoglobin precipitation and kidney damage.
Monitor Volume Status: Using diuretics in a dehydrated patient can worsen acute kidney injury; they should only be considered in patients with adequate intravascular volume.
High Urine Output is the Goal: The primary therapeutic goal is to achieve and maintain a high urine output (e.g., 200-300 mL/hr) primarily through aggressive hydration.

Understanding Rhabdomyolysis and Kidney Risk

Rhabdomyolysis is a serious syndrome resulting from the breakdown of skeletal muscle fibers, which releases damaging intracellular contents into the bloodstream. One of the most dangerous components released is myoglobin, a protein that can be toxic to the kidneys. When myoglobin overwhelms the kidney's filtering capacity, it can precipitate in the renal tubules, causing obstruction and direct cellular damage. This process, combined with dehydration and renal vasoconstriction, can lead to acute kidney injury (AKI), a life-threatening complication occurring in 17-35% of adult rhabdomyolysis cases.

The primary goals of treatment are to preserve kidney function and correct dangerous electrolyte imbalances, such as hyperkalemia (high potassium). The undisputed cornerstone of managing rhabdomyolysis and preventing AKI is early and aggressive intravenous (IV) fluid resuscitation. By administering large volumes of crystalloid solutions like normal saline, clinicians aim to dilute the myoglobin, flush it through the kidneys, and maintain a high urine output, ideally between 200 to 300 mL/hour in adults.

The Controversial Role of Diuretics

The use of diuretics is one of the most debated topics in rhabdomyolysis management. While forcing diuresis (increased urine production) seems like a logical way to prevent tubular obstruction, the evidence supporting the routine use of diuretics is limited and conflicting. Some clinical guidelines explicitly do not recommend their use for the prevention of AKI due to a lack of high-quality evidence from controlled trials. Their use is generally reserved for specific situations, not as a first-line therapy.

The main indication for considering diuretics is when a patient has inadequate urine output (oliguria) despite what is deemed to be adequate or aggressive fluid resuscitation. In these cases, a clinician might carefully administer a diuretic to provoke urine flow. However, this must be done with extreme caution, as using diuretics in a fluid-depleted (hypovolemic) patient can worsen kidney injury.

Specific Diuretics in Rhabdomyolysis

When diuretics are considered, two main types are discussed: osmotic diuretics (mannitol) and loop diuretics (furosemide).

Mannitol (Osmotic Diuretic)

Mannitol is an osmotic diuretic that draws water into the renal tubules, increasing urine flow. Theoretical benefits include flushing myoglobin casts, renal vasodilation, and potentially scavenging free radicals. Evidence of superiority over aggressive fluid therapy is limited. Mannitol is discouraged in anuric patients and carries risks like congestive heart failure and osmotic nephrosis.

Furosemide (Loop Diuretic)

Furosemide is a potent loop diuretic. It may be used in oliguric patients with adequate or excess fluid volume. Its use is controversial due to potential downsides like acidifying urine, which could promote myoglobin precipitation and obstruction. It may also worsen renal vasoconstriction and cause electrolyte imbalances.

Comparison of Treatment Strategies


Strategy	Mechanism of Action	Pros	Cons	Clinical Guideline Stance
Aggressive IV Fluids Alone	Dilutes myoglobin, increases renal perfusion, flushes tubules.	Cornerstone of therapy, proven benefit in minimizing AKI.	Risk of volume overload.	Universally Recommended.
IV Fluids + Mannitol	Osmotic diuresis, renal vasodilation.	May increase urine flow when fluids alone fail.	No proven benefit over fluids alone; risk of osmotic nephrosis and volume overload; contraindicated in anuria.	Not Routinely Recommended.
IV Fluids + Furosemide	Potent diuresis.	Can treat volume overload; increases urine output in euvolemic/hypervolemic patients.	Acidifies urine, potentially worsening myoglobin precipitation; risk of electrolyte depletion and hypovolemia.	Not Routinely Recommended for AKI prevention.

Conclusion

The answer to what diuretics are used for rhabdomyolysis is complex. While mannitol and furosemide are sometimes considered, their role is secondary and controversial. Aggressive IV fluid hydration is the foundation of management. Diuretics are not routinely recommended to prevent AKI. Their use is reserved for specific situations like inadequate urine output despite fluid resuscitation or managing fluid overload. Risks like worsening kidney injury or electrolyte disturbances mean they require cautious use. Further research is needed.

For further reading, a comprehensive clinical consensus document on rhabdomyolysis management can be found here: Rhabdomyolysis: an American Association for the Surgery of Trauma Critical Care Committee clinical consensus document

Frequently Asked Questions

The first-line and most critical treatment for rhabdomyolysis is early and aggressive intravenous (IV) fluid resuscitation with a crystalloid solution like normal saline to protect the kidneys.

No, mannitol is not always used. Its use is controversial and not routinely recommended. It is considered only in specific cases, such as for patients who fail to produce adequate urine despite aggressive fluid therapy.

Furosemide is not routinely recommended because it can acidify the urine, which may promote the precipitation of myoglobin in the kidney tubules and worsen kidney injury. The evidence supporting its use is very limited.

Yes, if used improperly. Administering diuretics to a dehydrated patient can worsen kidney injury. Furthermore, loop diuretics can cause electrolyte imbalances like hypokalemia, which is a potential cause of rhabdomyolysis itself.

Forced diuresis refers to promoting a high rate of urine flow. While this term was historically associated with using diuretics, current practice emphasizes achieving this primarily through aggressive IV fluid administration. The use of diuretics to force urination is now a controversial secondary option.

The combination of sodium bicarbonate (to make urine less acidic) and a diuretic like mannitol has been used historically, but its effectiveness is highly debated. Current evidence does not show a clear benefit over aggressive IV fluids alone, and its routine use is not recommended by many guidelines.

A doctor might consider a diuretic in two main situations: 1) if the patient's urine output remains low despite receiving large volumes of IV fluids, or 2) if the patient develops signs of fluid overload (like pulmonary edema) from the aggressive hydration.