Furosemide

It is a sulfonamide diuretic. Its chemical name is 4-Chloro-N-furfuryl-5-sulfamoylanthranilic acid.
Action:
It blocks sodium-potassium-chloride cotransporter in thick ascending limb of the loop of Henle resulting in the inhibition of the water reabsorption. It increases renal blood flow and causes redistribution of blood flow within renal cortex.

Administration and dosage:

Furosemide can be administered orally, IM or intravenously. Its usual dosage is 20-50 mg per day.
Pharmacokinetics:
It is excreted renally. Its onset of action is 30 minutes to 60 minutes and duration of action is 2 hours (when administered IV) and 6-8.5 hours (when administered orally).

Therapeutic uses:
1. Edematous states from congestive heart failure or some renal disease
2. Hypertension
3. To increase serum calcium level
4. It is a diuretic.

Adverse effects:
Light-headedness, dizziness, thirst, weakness

Interaction:
Furosemide and bumetanide weakly inhibit carbonic anhydrase.