Bumetanide (Bumex) | Medication Reference

Bedside Snapshot

Core dose: IV bolus 0.5–1 mg slow IV push, may repeat every 2–3 h (max 10 mg/day); continuous infusion 0.5–2 mg/h after bolus; oral 0.5–2 mg once daily
Onset/duration: IV onset 2–3 min, peak ~5 min; oral onset 30–60 min; duration 4–6 hours; half-life ~1–1.5 h
Key danger: Profound diuresis → hypokalemia, hypomagnesemia, hypotension, dehydration; ototoxicity (usually reversible); absolutely avoid in anuria or severe uncorrected electrolyte depletion
Special: Loop diuretic ~40× more potent than furosemide (1 mg bumetanide ≈ 40 mg furosemide); inhibits NKCC2 in loop of Henle; promotes K⁺, Mg²⁺, Ca²⁺ loss; alternative when furosemide allergy/resistance

Brand & Generic Names

Generic Name: Bumetanide
Brand Names: Bumex (U.S.); Burinex (international markets)

Medication Class

Loop diuretic

Pharmacology

Mechanism of Action:

Inhibits the Na⁺–K⁺–2Cl⁻ cotransporter (NKCC2) in the thick ascending limb of the loop of Henle
Increases excretion of sodium, chloride, and water
Promotes urinary loss of potassium, calcium, and magnesium

Pharmacokinetics:

Absorption: Oral bioavailability 59–89%
Onset: IV 2–3 minutes; PO/IM 30–60 minutes
Peak: IV ~5 minutes; IM ~30 minutes; PO 1–2 hours
Duration: 4–6 hours
Distribution: Protein binding 94–96%; Volume of distribution 9–25 L (adults)
Metabolism: Partial hepatic metabolism to inactive conjugates and desbutyl metabolites
Elimination: Half-life ~1–1.5 hours in adults (prolonged in infants/neonates); primarily excreted in urine (~81%)

Indications

Primary indications: Edema due to heart failure, hepatic cirrhosis, or renal disease (including nephrotic syndrome)
Acute decompensated heart failure with volume overload (IV bolus or infusion)
Alternative when furosemide allergy or intolerance is present
Off-label uses: Adjunct in hypertension with volume overload or diuretic resistance when other loop diuretics are ineffective

Conditions Treated

Congestive heart failure (CHF) with volume overload
Acute decompensated heart failure (ADHF)
Hepatic cirrhosis with ascites
Renal disease with edema
Nephrotic syndrome
Hypertension with volume overload (off-label)

Dosing & Administration

Available Forms:

Tablets: 0.5 mg, 1 mg, 2 mg
Injection: 0.25 mg/mL (IV/IM)

Standard Adult Dosing:

Route	Initial Dose	Repeat Dosing	Maximum
Oral	0.5–2 mg once	May repeat in 4–5 hr for up to 2 doses	10 mg/day
IM	0.5–1 mg	May repeat every 2–3 hr for up to 2 doses	10 mg/day
IV Bolus	0.5–1 mg slow IV push	May repeat every 2–3 hr based on response	10 mg/day
IV Continuous Infusion	1–4 mg IV bolus initially	Then 0.5–1 mg/hr infusion	Typical ceiling 2 mg/hr

Dose Equivalence: 1 mg bumetanide ≈ 40 mg furosemide ≈ 20 mg torsemide (PO equivalents)

Continuous Infusion Titration: Titrate infusion to urine output and hemodynamics. Target urine output typically >150–200 mL/hr or individualized based on patient needs. Adjust infusion rate and consider adding thiazide synergy if inadequate response.

Contraindications

Absolute Contraindications:

Hypersensitivity to bumetanide or sulfonamides
Anuria (complete absence of urine production)
Severe uncorrected electrolyte depletion
Hepatic coma

Precautions:

Risk of profound diuresis and electrolyte loss
Monitor closely in renal or hepatic impairment
Use with caution in elderly patients
Ototoxicity risk increases with:
- Rapid IV push
- High doses
- Renal dysfunction
- Co-administration with aminoglycosides or other nephrotoxic/ototoxic agents

Warning: Ototoxicity risk is heightened with rapid IV administration, high doses, renal dysfunction, or concurrent use of aminoglycosides. Administer slowly and monitor hearing.

Adverse Effects

Common:

Hypokalemia (low potassium)
Hypomagnesemia (low magnesium)
Hyponatremia (low sodium)
Metabolic alkalosis
Hypocalcemia (low calcium)
Hyperuricemia (elevated uric acid)
Hyperglycemia (elevated blood glucose)
Hypotension
Dizziness or muscle cramps

Serious:

Ototoxicity (usually reversible, but can be permanent)
Severe volume depletion
Acute kidney injury (AKI) or azotemia
Severe dermatologic reactions (e.g., Stevens-Johnson syndrome [SJS], toxic epidermal necrolysis [TEN])
Blood dyscrasias (rare)

Drug Interactions

Aminoglycosides (gentamicin, tobramycin, amikacin): Additive ototoxicity and nephrotoxicity—avoid or monitor closely
NSAIDs: May blunt diuretic response by reducing renal prostaglandins; monitor efficacy and renal function
ACE inhibitors / ARBs / other antihypertensives: Additive hypotension and AKI risk when combined in volume-depleted states
Lithium: Loop diuretics can increase lithium levels and toxicity—generally avoid or monitor lithium levels closely
Digoxin: Hypokalemia from loop diuretics increases digoxin toxicity risk—maintain potassium and magnesium levels
Other diuretics (thiazides, metolazone): Synergistic natriuresis—use for diuretic resistance with careful electrolyte monitoring

Aminoglycoside Warning: Concurrent use of aminoglycosides with bumetanide significantly increases risk of ototoxicity and nephrotoxicity. Avoid combination when possible or monitor closely with therapeutic drug levels.

Monitoring

Clinical Monitoring:

Strict intake and output (I/O)
Daily weights
Edema assessment and lung examination
Blood pressure and perfusion status
Hearing changes (especially with rapid IV dosing, renal dysfunction, or aminoglycoside co-administration)

Laboratory Monitoring:

Serum electrolytes—K⁺, Mg²⁺, Na⁺, bicarbonate
Renal function (BUN/Creatinine)
Uric acid
Glucose

Continuous Infusion Monitoring:

Urine output targets (e.g., >150–200 mL/hr or individualized)
Adjust infusion rate based on response
Add thiazide synergy if inadequate response

References

Medscape. (2025). Bumetanide (Bumex, Burinex) monograph. Retrieved November 11, 2025, from https://reference.medscape.com/drug/bumex-burinex-bumetanide-342421
U.S. Food and Drug Administration. (2024). Bumex (bumetanide) [Prescribing information]. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/018225Orig1s029lbl.pdf
Martin, S. J., & Dasta, J. F. (2006). Pharmacologic management of acute heart failure. In Critical Care Clinics (Vol. 22, No. 6). Elsevier.

Clinical Pearls

Better Oral Bioavailability: Bumetanide has more predictable oral bioavailability (59–89%) compared to furosemide (10–90%). This makes it particularly helpful when gut edema impairs furosemide absorption in heart failure patients.

Continuous Infusion Strategy: Consider continuous infusion after a bolus to overcome diuretic resistance and reduce ototoxic peak concentrations. This provides more consistent diuresis with fewer adverse effects.

Dose Equivalence: Remember the 40:1 ratio—1 mg bumetanide ≈ 40 mg furosemide. Avoid exceeding practical ceiling doses; instead, add thiazide synergy (e.g., metolazone) for diuretic resistance.

"Sulfa" Allergy: Cross-reactivity with loop diuretics in sulfa allergy is uncommon but possible. If true sulfonamide allergy exists and cross-reactivity is a concern, ethacrynic acid is a non-sulfonamide loop diuretic alternative.

Cirrhosis Caution: In patients with cirrhosis, avoid over-diuresis as it can precipitate hepatic encephalopathy and acute kidney injury. Consider spironolactone as the primary diuretic for ascites management in cirrhotic patients.

Electrolyte Vigilance: Loop diuretics cause significant potassium and magnesium wasting. Monitor and replete aggressively, especially in patients on digoxin where hypokalemia increases toxicity risk.

Diuretic Resistance Strategy: When patients don't respond to adequate loop diuretic doses, add sequential nephron blockade with a thiazide (metolazone 2.5–5 mg PO daily). This blocks distal tubule compensation and provides synergistic diuresis. Monitor electrolytes closely.