Diuretics

Question 1

As a class, Diuretics are used in the management of:

Answer 1

Edema
Hypertension
Cardiovascular and/or renal disease
Glaucoma

Question 2

These drugs all act in the nephron to cause

Answer 2

diuresis

Question 3

diuresis

Answer 3

Increased urine production

Question 4

Classes of diuretics

Answer 4

Thiazide–Hydrochlorothiazide
Loop–Furosemide
Potassium-Sparing–Spironolactone, triamterene
Osmotic–Mannitol
Carbonic Anhydrase Inhibitors–Acetazolamide, dorzolamide

Question 5

MOA of hydrochlorothiazide

Answer 5

Hydrochlorothiazide (HCTZ)

MoA: Inhibition of the Na+,Cl- symporter in the early portion of the distal tubule, which leads to a decreased resorption of these ions.
Increases sodium and water excretion

Question 6

HCTZ is used in the treatment of

Answer 6

Used in the treatment of HTN,
diabetes insipidus,
nephrolithiasis

Question 7

ADR of HCTZ:

Answer 7

hypotension, 
dizziness, 
hypokalemia, 
hyponatremia, 
increased blood glucose
The hypokalemia can bring about metabolic alkalosis and reduced insulin secretion (hyperglycemia)

“Sulfa allergy”—the presence of a sulfonamide functional group in a drug molecule can trigger an anaphylactic response in some patients

Question 8

drug interactions of HCTZ

Answer 8

potentiates the effect of loop diuretics.

hypokalemia exacerbates digoxin toxicity

Question 9

Loop diuretics

Answer 9

Furosemide

Question 10

Mechanism of action of loop diuretics

Answer 10

Inhibition of the Na+,K+,2Cl- symporter in the ascending limb of the loop of Henle.

Increases sodium and water excretion…more so than other diuretics

Question 11

loop diuretics is used in the treatment

Answer 11

Used in the treatment of cirrhosis,
HF,
hypercalcemia,
pulmonary edema, and renal disease

Question 12

ADR of loop diuretics

Answer 12

ADRs include: hypotension, 
dizziness, 
hypokalemia, 
hyponatremia, 
hypocalcemia,
 (reversible) ototoxicity

The hypokalemia can bring about metabolic alkalosis
“Sulfa allergy”

Question 13

Drug interactions of Loop diuretics

Answer 13

Drug Interactions: hypokalemia can exacerbate digoxin toxicity,
hypotensive effects synergistic with other anti-hypertensives

Question 14

potassium sparing diuretics

Answer 14

Amiloride,triamterene,spironolactone

Question 15

Amiloride and triamterene MOA

Answer 15

MoA: Sodium channel blockers preventing reabsorption at the late distal tubule and collecting duct, which indirectly reduces the secretion of potassium into the tubular filtrate and urine

Question 16

Spironolactone

Answer 16

MoA: Aldosterone antagonist at the late distal tubule and collecting duct, which blocks gene expression ultimately prevents sodium reabsorption and potassium secretion

Question 17

potassium sparing drugs are used in the treatment of

Answer 17

These drugs are used to treat or prevent hypokalemia

Question 18

ADR of potassium sparing drugs

Answer 18

ADRs include: hypotension, dizziness, hyperkalemia

Spironolactone has an antiandrogenic effect, and can cause gynecomastia and impotence in men.

Question 19

Drug interactions of Potassium sparing drugs

Answer 19

Drug Interactions: Administration with ACE inhibitors, ARBs, or potassium supplements can cause hyperkalemia

Question 20

Osmotic diuretics

Answer 20

Mannitol and Glycerol

Question 21

Mannitol route of administration (ROA)

Answer 21

IV

Question 22

Glycerol ROA

Answer 22

PO

Question 23

Osmotic diuretics MOA

Answer 23

They are filtered in the glomerulus
They are not reabsorbed from renal tubule
they osmotically attract water
they retain water in the nephron and in the urine
They also increase the osmotic pressure in the interstitial and trans cellular fluid.

Question 24

Osmotic diuretics are used in the treatment of

Answer 24

cerebral edema
acute renal failure
Acute Glaucoma

Question 25

ADR of osmotic diuretics

Answer 25

increase in plasma volume
exacerbation of heart failure
edema

Question 26

Drug interactions

Answer 26

potentiates the effect of other diuretics

Question 27

Carbonic anhydrase inhibitors

Answer 27

Acetazolomide and dorzolomide

Question 28

MOA of CAI

Answer 28

These drugs inhibit carbonic anhydrase (CA) throughout the body.
CA is required for reabsorption of sodium bicarbonate from the proximal tubule, thus its inhibition alkalinizes the urine and produces mild diuresis.

These drugs are rarely used as diuretics

Question 29

ophthalmic dorzolomide uses

Answer 29

Ophthalmic dorzolamide is used for glaucoma, as inhibition of CA in the eye reduces aqueous humor secretion and intraocular pressure

Question 30

ADR of CAI

Answer 30

ADRs include: metabolic acidosis,
drowsiness,
hypokalemia

Question 31

Acetazolomide is used to combat

Answer 31

Respiratory alkalosis durng mountain climbing

Question 32

ROA od CAI

Answer 32

Acetazolomide-oral

DOrzolomide-ophthalmic solution

Question 33

Drug Interactions of CAI

Answer 33

By alkalinizing the urine, these drugs can decrease the excretion of weak bases (amphetamines, catecholamines, etc.)
In alkaline urine,weak bases are not ionized and will not readily dissolve in water and as a result they are not excreted through urine as they cannot pass through the membrane.