Diuretics Flashcards
What are the osmotic diuretics
Glycerin
Urea
Mannitol
Isosorbide
How is Mannitol given
Injection (oral is not absorbed)
What is mannitol used for
Localized edema
Where do osmotic diuretics act upon
Ascending loop of henle
Proximal tubule
How is mannitol excreted
Rapidly by the kidney
Why is mannitol not given orally
Very hydrophilic
Not metabolized
Osmotic Diuretics are used for
Cerebral edema
Glaucoma
Acute renal failure
Drug overdose
Osmotic Diuretics interfere with the excretion of
Na, Ca, K, Mg, Cl, HCO2, Phosphate
How do Loop Diuretics work
Inhibit Na-K 2Cl symporter at luminal membrane
Inhibits paracellular reabsorption of Na, Ca, Mg
What can Loop Diuretics cause
Hypokalemia Alkalosis Increase glucose Ototoxicity Hypotension
What are loop diuretics used for
Acute pulmonary edema/congestion Gen. edema w/ CHF Chronic renal failure Liver cirrhosis Drug overdose
How is furosemide given
Oral or IV
What is the onset and duration of furosemide
Rapid onset
Short duration
Furosemide is used for what in horses
EIPH - Exercise Induced Pulmonary Hemorrhage
What are the Loop Diuretics
Furosemide
Bumetanide
Ethacrynic acid
Where do Thiazide Diuretics work
Distal Convoluted Tubule
How do Thiazide Diuretics work
Inhibit Na-Cl symporter –> inhibits reabsorption, causes diuresis
Thiazide diuretics decrease reabsorption of
K and Mg
Thiazide diuretics increase reabsorption of
Ca
Thiazide diuretics are used to treat what
CHF edema, liver cirrhosis, nephrotic syndrome, acute glomerular nephritis
Hypertension
Nephrogenic DI
How are thiazide drugs given and how is there absorption
orally
Slow and incomplete absorption
Thiazide drugs are excreted by
Kidneys
Urine
Where do Potassium Sparing Diuretics act
Late distal tubule
What is the major potassium sparing diuretic
Spironolactone
How is Spironolactone given and how is its absorption
Orally
Readily absorbed
How does Spironolactone work
Competitive antagonist of aldosterone –> decreases Na and increases K, decrease water retention
Is Spironolactone metabolized
Yes - converted to active metabolite in the liver
What is the onset and duration for Spironolactone
Slow onset
Long duration
Adverse effects of Spironolactone
Hyperkalemia
Acidosis
Progesterone and androgen levels
What is Spironolactone used for
Primary and secondary hyperaldosteronism