Diuretics

Question 1

CA inhibitors

Answer 1

Acetazolamide
Dorzolamide (topical)
Brinzolamide (topical)

Question 2

Where do CA inhibitors work

Answer 2

proximal tubule

Question 3

Use of CAI

Answer 3

Bicarb diuresis
Alkalinization of urine (increase weak acid excretion) alkalosis (metabolic or respiratory)
Moutain sickness (resp alkalosis)
GLAUCOMA (topicals) – dec CSF and aqueous humor

Question 4

Kinetics of CAI

Answer 4

renal excretion: dose adjust in renal insufficiency
oral absorption (30 min)
not used as long term diureti - H accumulation

Question 5

Why is CAI not used as long term diuretics

Answer 5

metabolic process eventually cause H+ to build up in cell and eventually NHE will begin to work again

Question 6

SE of CAI

Answer 6

Hyperchloremic metabolic acidosis (excreted as NaHCO3)
Hypokalemia (Na/K ATPase)
Renal stones (inc. calcium in urine)
Hyperuricemia (compete)

Question 7

Contraindications for CAI

Answer 7

hepatic cirrhosis (alkalinization of urine decreases ammonia excretion)
sulfonamide hypersensitivity

Question 8

Loop diuretics

Answer 8

Furosemide
Bumetanide
Torsemide
Ethacrynic acid

Question 9

Which loop diuretic is not a sulfa?

Answer 9

Ethacrynic acid

Question 10

What works best at low GFR?

Answer 10

loop diuretics

Question 11

Use of loop diuretics

Answer 11

HF
Pulmonary edema (vasodilator effect)
Edema due to impaired renal function
HYPERCALCEMIA

Question 12

MOA of loops

Answer 12

Inhibit NKCC2, thereby also inhibit Mg and Ca absorption

Induce kidney PGs (vasodilation, decreases salt transport)

Question 13

SE of loop diuretics

Answer 13

High potentcy- abnormal fluid and electrolytes
HYPOKALEMIC METABOLIC ALKALOSIS (Na/K and Na/H in distal tubule exchange)
Hypocalcemia and hypomagneseia
Hyperuricemia
GI
IRREVERSIBLE OTOTOXCITY

Question 14

Worse ototoxicity

Answer 14

ethacrynic acid

Question 15

Ototoxicity is worse when given with

Answer 15

amingolycosides

Question 16

Contraindictions of loops

Answer 16

sulfa allergy (except ethacrynic acid)
Drug interactions

Question 17

Overzealous use of loops is dangerous in

Answer 17

Hepatic cirrhosis
borderline renal failure
HF

Question 18

Drug interactions of loop

Answer 18

COX inhibitors (PG synthesis required- vasodilation)
aminoglycoside (ototoxic)
litium (loss of Na increases Li retention and toxicity)
Digoxin (loss of K increases toxicity)

Question 19

Most widely used diuretic

Answer 19

thiazides

Question 20

Dependent on PG synthesis

Answer 20

CAI

Thiazides

Question 21

Thiazide drugs

Answer 21

Hydrochlorothiazide
Chlorothiazide
Chlorthalidone
Metolazone
Indapamide
Quinethazone

Question 22

MOA of thiazide

Answer 22

inhibit NCC in early distal tubule (Na-Cl symporter)

Inc. ATP-dep K+ channel opening- vasodilation (dec. insulin secretion)

effect dependent on PG synthsis

Question 23

Use of thiazides

Answer 23

HTN!
HF - not as effective as loops
nephrolithiasis - dec Calcium excretion due to increaed activity of PTH-dep calcium channels (Na pushes Ca through)
nephrogenic DI

Question 24

Thiazide with longest duration

Answer 24

Chlorthalidone (preffered because of this)

Question 25

Indapamide

Answer 25

Excreted 50/50 liver and kidney (renal insufficiency) No increase in lipid levels Vasodilation (CCB)

Question 26

Good thiazide for renal insufficiency

Answer 26

indapamide

Question 27

SE of thiazides

Answer 27

``` Hypokalemic metabolis alkalosis Hyperuricemia Magnesium loss Iodide/bromide loss HYPERGLYCEMIA Elevated lipid levels (except indapamide) ```

Question 28

Contra to thiazides

Answer 28

``` sulfa inhibited by NSAIDs (depend on PG) Digitalis (hypkalemia) Diabetics (hyperglycemia) Lithium (low Na) ```

Question 29

Metolazone

Answer 29

produces diuresis in patients w/ reduced GFR (exception to the thiazides)

Question 30

Used in low GFR

Answer 30

loop diuretics | Metolazone (thiazide)

Question 31

Classes of potassium sparing diuretics

Answer 31

aldosterone antagonist | direct inhibitor of Na flux

Question 32

Where do potassium sparing diuretics work

Answer 32

distal tuble/CD

Question 33

DOC for lithium induced DI

Answer 33

Amiloride

Question 34

Do not cause hyperuricemia

Answer 34

Amiloriide | Triameterene

Question 35

MOA of Amiloride, triamterene

Answer 35

inhibit eNaC channel in distal tubule/CD -

Question 36

SE of amiloride and triamterene

Answer 36

Hyperkalemia (chronic or in combo w/ other K sparing) | N/V/leg cramps dizziness

Question 37

Contra of amiloride/triamterone

Answer 37

Hyperkalemia (burns)

Question 38

Not dependent on sodum

Answer 38

mannitol, isosorbide, glycerin, urea (osmotic diuretics)

Question 39

DOC for central DI

Answer 39

Desmopressin

Question 40

SE of desmopressin

Answer 40

hyponaremia | GI, H/a, dizziness, allergic reaction

Question 41

SIADH DOC

Answer 41

Conivaptan or tolvaptan (outpatient)

Question 42

Conivaptan administration

Answer 42

IV only

Question 43

Tolvaptan administration

Answer 43

oral, send home on medication

Question 44

Contraindication of vaptans

Answer 44

Hypovolemic hyponatremia