Furosemide is a loop diuretic.
- Inhibits the reabsorption of sodium and chloride from the loop of Henle and distal renal tubule.
- Increases renal excretion of water, sodium, chloride, magnesium, potassium, and calcium.
- Effectiveness persists in impaired renal function.
Pharmacokinetics
- Absorption: 60–67% absorbed after oral administration (↓ in acute HF and in renal failure); also absorbed from IM sites; IV administration results in complete availability; 99.6% absorbed after SUBQ administration.
- Protein Binding: 91–99%.
- Metabolism and Excretion: Minimally metabolized by liver, some non-hepatic metabolism, some renal excretion as unchanged drug.
- Half-life: 30–120 min (↑ in renal impairment).
