Bumetanide

Loop diuretics are potent diuretics; excess amounts can lead to profound diuresis with fluid and electrolyte loss; close medical supervision and dose evaluation are required. Potassium supplementation and/or use of potassium-sparing diuretics may be necessary to prevent hypokalemia. In contrast to thiazide diuretics, a loop diuretic can also lower serum calcium concentrations. Electrolyte disturbances can predispose a patient to serious cardiac arrhythmias.

Asymptomatic hyperuricemia has been reported with use.

Monitor fluid status and renal function in an attempt to prevent oliguria, azotemia, and reversible increases in BUN and creatinine; close medical supervision of aggressive diuresis required.

Bumetanide-induced ototoxicity (usually transient) may occur with rapid IV administration, renal impairment, excessive doses, and concurrent use of other ototoxins (eg, aminoglycosides).

The FDA-approved product labeling for many medications containing a sulfonamide chemical group includes a broad contraindication in patients with a prior allergic reaction to sulfonamides. There is a potential for cross-reactivity between members of a specific class (eg, two antibiotic sulfonamides). However, concerns for cross-reactivity have previously extended to all compounds containing the sulfonamide structure (SO2NH2). An expanded understanding of allergic mechanisms indicates cross-reactivity between antibiotic sulfonamides and nonantibiotic sulfonamides may not occur or at the very least this potential is extremely low (Brackett 2004; Johnson 2005; Slatore 2004; Tornero 2004). In particular, mechanisms of cross-reaction due to antibody production (anaphylaxis) are unlikely to occur with nonantibiotic sulfonamides. T-cell-mediated (type IV) reactions (eg, maculopapular rash) are less well understood and it is not possible to completely exclude this potential based on current insights. In cases where prior reactions were severe (Stevens-Johnson syndrome/TEN), some clinicians choose to avoid exposure to these classes. Disease-related concerns:

Use caution in patients with cirrhosis; initiate bumetanide therapy with conservative dosing and close monitoring of electrolytes; avoid sudden changes in fluid and electrolyte balance and acid/base status which may lead to hepatic encephalopathy.

Larger doses may be necessary in patients with impaired renal function to obtain the same therapeutic response (Brater 1998). Concurrent drug therapy issues:

Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information. Special populations:

In vitro studies using pooled sera from critically-ill neonates have shown bumetanide to be a potent displacer of bilirubin; avoid use in neonates at risk for kernicterus.

If given the morning of surgery, bumetanide may render the patient volume depleted and blood pressure may be labile during general anesthesia. Dosage form specific issues:

Some dosage forms may contain benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol with caution in neonates. See manufacturer’s labeling. Other warnings and precautions:

For some patients, despite higher doses of loop diuretic treatment, an adequate diuretic response cannot be attained. Diuretic resistance can usually be overcome by intravenous administration, the use of two diuretics together (eg, furosemide and chlorothiazide), or the use of a diuretic with a positive inotropic agent. When such combinations are used, serum electrolytes need to be monitored even more closely (ACC/AHA [Yancy, 2013]; HFSA, 2010).