torsemide
Brand: Demadex
Prototype: furosemide
Drug Class: loop diuretic
Drug Family: diuretic
Subclass: pyridine-sulfonylurea loop diuretic
Organ Systems: cardiovascularrenal
Mechanism of Action
Inhibits NKCC2 in thick ascending limb; not a sulfonamide; more consistent oral bioavailability than furosemide.
NKCC2 cotransporter
Indications
- edema
- heart failure
- hypertension
Contraindications
- anuria
Adverse Effects
Common
- hypokalemia
- hypotension
- dizziness
Serious
- ototoxicity (less than furosemide)
- electrolyte disturbances
Pharmacokinetics (ADME)
| Absorption | 80-90% consistent oral bioavailability |
| Distribution | moderate |
| Metabolism | extensive hepatic CYP2C9 (80%) |
| Excretion | renal 20% unchanged |
| Half-life | 3.5 hours |
| Onset | 1 hour |
| Peak | 1-2 hours |
| Duration | 6-8 hours |
| Protein Binding | >97% |
| Vd | 12-15 L |
Drug Interactions
| Drug / Agent | Mechanism | Severity |
|---|---|---|
| digoxin | hypokalemia increases toxicity | major |
| NSAIDs | reduced diuretic response | moderate |
Nursing Considerations
- More reliable bioavailability than furosemide — useful in refractory HF
- Once-daily dosing possible
- Not a sulfonamide — use in patients with sulfa allergy
- TRANSFORM-HF: similar outcomes to furosemide in acute decompensated HF
Clinical Pearls
- TRANSFORM-HF trial: torsemide not superior to furosemide for 12-month mortality
- Not a sulfonamide derivative — no sulfa cross-reactivity
Safety Profile
Pregnancy use-with-caution
Lactation avoid
Renal Adjustment Required
Hepatic Adjustment Required
TDM Not required
Concordance Terms
Cross-referenced clinical concepts — click any term to see all content where it appears.