Diuretic Drugs Flashcards
What are diuretic drugs?
Drugs that accelerate the rate of urine formation
What do diuretics drugs result in?
Removal of sodium and water from the body
What returns 60 - 70% of sodium back into the bloodstream
PCT
What returns 20 - 25% of sodium back into the bloodstream
Loop of Henle
What returns 5 - 10% of sodium back into the bloodstream
DCT
What happens if water is not absorbed?
It is excreted as urine
What are the 5 types of Diuretic Drugs?
Carbonic anhydrase inhibitors
Loop Diuretics
Osmotic Diuretics
Potassium-sparing diuretics
Thiazide and Thiazide-like diuretics
Name a carbonic anhydrase inhibitor (CAI)
Acetazolamide
What is acetazolamide also used for?
Glaucoma
What is the MOA of acetazolamide
Carbonic anhydrase makes Hydrogen available for exchange with sodium and water in the proximal tubules
CAIs block this action resulting in an increased excretion of bicarbonate, sodium, water, and potassium
What are the indications of CAIs
Used adjunctly in the long-term treatment of open-angle glaucoma
Used with miotics (constriction of pupils) to lower intraocular pressure before ocular surgery
Edema resulting from HF
High altitude sickness
Epilepsy
What are the contraindications of CAIs
Hyponatremia
Hypokalemia
Severe liver or kidney dysfunction
Adrenal gland insufficiency
Cirrhosis
What are the adverse effects of Acetazolamide
Acidosis
Hypokalemia
Drowsiness
Anorexia
Paresthesia
Hematuria
Urticaria
Photosensitivity
Melena (stool in blood)
What are possible interactions with CAIs
May cause an increase in digoxin toxicity
Hypokalemia with corticosteroids
Increase effects of amphetamines, carbamazepine, cyclosporine, phenytoin and quinidine sulphate
What is the MOA of furosemide
It acts directly on the ascending limb of the loop of Henle to block chloride and sodium resorption.
Increases kidney prostaglandins resulting in the dilation of blood vessels and reduced kidney, pulmonary and vascular resistance
What are the uses for loop diuretics
Edema associated with HF and liver or kidney disease
HTN
Kidney excretion
HF resulting from diastolic dysfunction
What are the adverse effects of loop diuretics
Dizziness, headache, tinnitus, blurred vision, Agranulocytosis, neutropenia, thrombocytopenia, Hypokalemia, Hyperuricemia, Hyperglycemia
What are the possible interactions of loop diuretics
NSAIDs may decrease the reduction of vascular resistance
Increase serum levels of uric acid, glucose, alanine aminotransferase and aspartate aminotransferase
What is the most commonly used loop diuretic?
Furosemide
What is the most commonly used osmotic diuretic
Mannitol
What is the MOA of mannitol?
Works along entire nephron but mostly PCT and descending loop of Henle
Pulls water into renal tubules from the surrounding tissues and inhibits resorption of water and solutes, thus producing diuresis
What are some of the effects of osmotic diuretics (not adverse effects)
Increase eGFR
Reduce intracranial pressure or cerebral edema associated with head trauma
Reduces excessive intraocular pressure
What are the indications for osmotic diuretics?
Early phase of acute kidney injury
Excretion of toxic substances
Reduce intracranial pressure
Cerebral edema
GU irrigant in the prep of patients for transurethral surgical procedures
What are the adverse effects of mannitol
Convulsions
Thrombophlebitis
Headaches, chest pains, tachycardia, blurred vision, chills and fever
