Educational use only. Drug cards are AI-assisted study material for NCLEX preparation.
Mechanism of action
Inhibits the Na+/K+/2Cl⁻ cotransporter in the thick ascending limb of the loop of Henle — the same target as furosemide, but roughly 40× more potent on a milligram basis (1 mg bumetanide ≈ 40 mg furosemide). Used for fluid overload when furosemide loses effect or oral absorption is unreliable.
Adverse effects
Life-threatening / NCLEX-tested
- Severe hypokalemia → cardiac arrhythmias (especially with digoxin)
- Profound hypotension and dehydration
- Ototoxicity (less than furosemide, but real with rapid IV push or high doses)
- Hyponatremia, hypomagnesemia, hypocalcemia, hypochloremic metabolic alkalosis
- Acute kidney injury from over-diuresis
- Sulfa-class allergy cross-reactivity
Side effects
Common — what to teach
- Frequent urination — schedule the morning dose, not at bedtime
- Dizziness, orthostatic hypotension
- Muscle cramps (often a clue to hypokalemia or hypomagnesemia)
- Hyperuricemia and gout flare
- Hyperglycemia
Food & drug interactions
Same profile as furosemide. With digoxin, bumetanide-induced hypokalemia drives toxicity. Lithium clearance falls — risk of lithium toxicity. NSAIDs blunt the diuretic effect. Aminoglycosides plus loop diuretics multiply ototoxicity. ACE inhibitors and ARBs amplify first-dose hypotension. Encourage potassium-rich foods (banana, orange, potato, spinach) unless contraindicated.
Nursing implications
Assessment, monitoring, patient teaching
- Daily weight at the same time and on the same scale — most reliable measure of fluid status
- Strict I&O, BP (lying and standing), and serum electrolytes — especially K+ and Mg++
- Push IV slowly (over 1–2 minutes) to reduce ototoxicity risk
- Give in the morning to avoid nocturia; if BID, give the second dose by mid-afternoon
- Teach hypokalemia signs (cramps, weakness, palpitations) and high-K+ foods
- Cross-check digoxin level when bumetanide is added
When to hold / contraindications
- Serum K+ < 3.5 mEq/L (correct first)
- SBP < 90 mmHg or symptomatic hypotension
- Anuria
- Significant hypovolemia or dehydration
- Worsening renal function without provider direction
Memory anchor
"Bumex is furosemide's stronger cousin — 1 mg = 40 mg Lasix." Same losses (K+, Na+, Mg++, Ca++, fluid), same monitoring, same daily-weight discipline.
Practice Bumetanide questions
Test your recall on real NCLEX-style pharmacology questions — with full rationales and an AI Coach for the parts you miss.