Diuretics Flashcards
What are diuretics
A drug or substance that increases the rate of urine secretion
What is the primary mechanism of Na+ transport in the proximal convoluted tubule
Na+/ H+ exchange
What are the classes of diuretics that work at the PCT
Carbonic anhydrase inhibitor
Osmotic diuretics
What is the prototypic agent of carbonic anhydrase inhibitors
Acetazolamide
MOA of acetazolamide
Inhibit of carbonic anhydrase in the brush border and cytoplasm
How is acetazolamide administered
Orally
Effects of acetazolamide
Metabolic acidosis
Potassium wasting (hypokalemia)
Acidosis of the cerebrospinal fluid causing hyperventilation
Clinical uses of acetazolamide
- Treatment of severe acute glaucoma
- Prevent acute mountain “high altitude” sickness
- Diuretic effect only if the edema is accompanied by metabolic alkalosis
Topical analogs for carbonic anhydrase inhibitors
- Dorzolamide
- Brinzolamide
Mention osmotic diuretics
- Mannitol
- Glycerol
- Isosorbide
How is Mannitol administered
Intravenously
MOA of mannitol
Increase concentration of solute in the tubular lumen and thus via osmosis promote excretion of water and electrolytes
Therapeutic use of mannitol
- Reduce raised intracranial pressure
- Reduce raised intraocular pressure in acute congestive glaucoma
- Maintain osmolarity of extracellular fluid during dialysis
Adverse reactions of Mannitol
Hyponatremia
Pulmonary edema
Headache, nausea, and vomiting
Mention loop diuretics
Furosemide
Bumetanide
Tiracemide
Ethacrynic acid