Bumetanide
Bumex
Loop diuretic
Inhibits the Na-K-2Cl cotransporter in the thick ascending limb → potent diuresis. ~40× more potent than furosemide (1 mg bumetanide ≈ 40 mg furosemide).
Indications
- •Edema/volume overload (HF, renal, hepatic)
- •Diuretic-resistant states
- •Better oral bioavailability than furosemide
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| IV | 0.5–1 mg IV (max ~10 mg/day); 1 mg ≈ 40 mg furosemide | — |
Pharmacokinetics
Onset minutes IV. Half-life ~1–1.5 h. More reliable oral absorption than furosemide.
Side effects
- !Hypokalemia, hypomagnesemia, hypovolemia, metabolic alkalosis
- !Ototoxicity (less than furosemide)
- !Hyperuricemia
Contraindications
- ×Anuria
- ×Severe electrolyte depletion
- ×Sulfonamide allergy (relative)
Clinical pearls
- ★1 mg bumetanide ≈ 40 mg furosemide — the conversion to know.
- ★More predictable oral absorption → used when furosemide's gut absorption is unreliable (gut edema in HF).
Other drugs in Diuretics
- Furosemide
Inhibits the Na-K-2Cl cotransporter in the thick ascending loop of Henle. Massive natriuresis + kaliuresis + magnesiuresis. Also a venodilator — drops preload within minutes, before diuresis kicks in.
- Mannitol
Freely filtered, not reabsorbed. Pulls water from tissues into vascular space (transient ↑intravascular volume) then drives osmotic diuresis. Reduces ICP by drawing water across an intact blood-brain barrier.
- Acetazolamide
Reversibly inhibits carbonic anhydrase in proximal renal tubule, choroid plexus, ciliary body, RBC. Renal effect: ↓Na/H exchange → bicarbonate diuresis + mild Na/water loss + metabolic acidosis. CNS effect: ↓CSF production. Eye effect: ↓aqueous humor.
- Spironolactone
Competitive antagonist at the mineralocorticoid receptor in the distal nephron → inhibits aldosterone-mediated Na reabsorption + K secretion. Net effect: mild Na/water loss + K retention + Mg retention. Also a weak androgen-receptor antagonist.
Browse all classes: /reference/drugs
Suggested reading
- •Stoelting & Hines, Pharmacology & Physiology in Anesthetic Practice, 6e
- •Miller's Anesthesia, 9e
- •FDA package insert
