Diuretics and Renally Acting Drugs

Question 1

Pharmacology of diuretics

Answer 1

• diuretics act only if Na+ reaches their site of action

- diuretics actions at difference nephron sites can produce synergism

Question 2

Mannitol site of action

Answer 2

All segments (mostly the loop of henle)

Question 3

Furosemide SoA

Answer 3

Thick ascending loop of henle

Question 4

Hydrochlorothiazide SoA

Answer 4

Distal tuble

Question 5

Spironolactone SoA

Answer 5

Distal tuble and collecting duct

Question 6

Acetazolamide SoA

Answer 6

Proximal tubule

Question 7

Osmotic diuretics characteristics

Answer 7

• freely filtered at the glomerulus
• hyperosmolatlity creates a water shift
• impairs passive water reabsoption

Question 8

When is mannitol used

Answer 8

-cases of cerebral edema and increase intracranial pressure (ICP)

Question 9

Mannitol Contraindicated

Answer 9

Causes of congestive heart failure

Question 10

Furosemide used for

Answer 10

Pulmonary edema due to CHF

• effective at love glomerular filtration rates
• increase potassium, Ca, and Mg excretion

Question 11

Non tubular effects of furosemide

Answer 11

• renal vasodilation and redistribution of blood flow
• increase in renin secretion
• increase in venous capacitance

Question 12

When is hydrochlorothiazide used

Answer 12

-refractory heart failure in combination with a loop diuretic

Question 13

How does hydrochlorothiazide work

Answer 13

• increase renal excretion of K and Mg
• reduce Ca and irate excretion
• not effective at low glomerular filtration rates

Question 14

Spirinolactone used in what cases

Answer 14

Primary hyperaldosteronism or cirrhosis

Question 15

Spirinolactone works by

Answer 15

Diminishing the degree of K+ loss

-poor diuretic

Question 16

Acetazolamide characteristics

Answer 16

• natriutesis and metabolic acidosis are self limiting
• weak diuretic
• treat glaucoma