Renal drugs

Question 1

Mannitol

Answer 1

Osmotic diuretic, increase tubular fluid osmolarity -> increase urine flow, decrease ICP, decrease IOP

Use: Drug overdose, elevated ICP/IOP
Tox: Pulmonary edema, dehydration, CI in anuria, HF

Question 2

Acetazolamide

Answer 2

Carbonic anhydrase inhibitor. Causes NaHCO3 diuresis -> Metabolic acidosis
Use: Glaucoma, urinary alkanilzation, metabolic alkalosis, respiratory alkalosis (altitude sickness), pseudomotor cerebri

Tox: hyperchloremic metabolic acidosis, sulfa allergy, NH3 toxicity

Question 3

Furosemide, Torsemide, Bumetanide

Answer 3

Loop diuretics
Moa: Sulfonamide loop diuretic. Inhibit cotransport (Na/K/ 2Cl) in thick ascending limb -> destroy the hypertonicity of medulla -> prevent concentration of urine

Stimulate PGE release; inhbited by NSAIDs; increase Ca excretion

Use: Edematous states (HF, cirrhosis, nephrotic syndrome, PE, HTN, hypercalcemia

Tox: Ototoxicity, Hypokalemia, Dehydration, sulfa allergy , interstitial nephritis, Gout

Question 4

Ethacrynic acid

Answer 4

NOT sulfonamide. Same action as furosemide

Use: diuresis in patients with sulfa drug allergy
Toxicity same as furosemide: Ototox, Hypokalemia, Dehydration, Hyperuricemia (Gout), no allergy to sulfa.

Question 5

Thiazide diuretics

Answer 5

Chlorthalidone, hydrochlorothiazide

Inhibit NaCl reabsorption in early DCT -> can’t dilute urine;
decrease Ca excretion
Use:
HTN, HF, IDIOPATHIC hypercalciuria, nephrogenic DI, osteoporosis

Tox: hypokalemia, contraction metabolic alkalosis, hyponatremia, Hyperglycemia, hyperlipidemia, hyperuricemia, hypercalcemia
Sulfa allergy

Question 6

K sparing diuretics

Answer 6

Spironolactone and eplerenone, Triamterene, Amiloride

Spironolactone and eplerenone are Aldosterone receptor antagonists. Eplerenone no gynecomastia

Triamterene and Amiloride - ENac Channel inhibitor in CD

Use: SIADH (hyperaldosteronism), K depletion, HF, CHF, and ascites

Tox: Hyperkalemia -> arrhythmias; gynecomastia by Spironolactone

Question 7

ACE inhibitors

Answer 7

-Prils, Lisinopril
Use: inhibit ACE-> decrease ATII-> decrease GFR
Renin level, AT1 level, Bradykinin increase (vasodilator)

USE: HTN, HF, Proteinuria (nephrotic syndrome), diabetic nephropathy. Prevent negative remodeling of heart in chronic HTN.

Tox: Cough, Angioedema, Teratogen (fetal renal malformation), increased Cr (decreased GFR), Hyperkalemia, and hypotension

CI in BILATERAL RENAL STENOSIS

Question 8

ARBs

Answer 8

-sartans

Blocks AT2 binding to AT1 receptors; No increase in Bradykinin

Use: HTN, HF, Proteinuria, diabetic nephropathy,

Tox: Hyperkalemia, decreasd renal function, hypotension, teratogen

Question 9

Aliskiren

Answer 9

Direct renin inhibitor, blocks Angiotensinogen to AT1
Use: HTN
Tox: Hyperkalemia, decreased renal function, hypotension

Question 10

Diuretics electrolyte changes

Blood pH

Answer 10

Acetazolamide, K sparing diuretics -> decrease blood pH
Aldosterone blockers prevent K and H secretion at CD. Also, Hyperkalemia -> more H out of cell and K into cell

Loop and Thiazide diuretics increase blood pH.
Thiazides -> volume contraction -> Increased AT2 -> increase Na/H transporters at PCT -> H secreted and Bicarb reabsorbed = contraction alkalosis

Question 11

Diuretics electrolyte changes

Urine NaCl

Answer 11

Loop diuretics, thiazides, K sparing diuretics increase urine NaCl
EXCEPT acetazolamide

Question 12

Diuretics electrolyte changes
Urine K
Urine Ca

Answer 12

Urine K Increase with loop and thiazide diuretics

Urine Ca increase: loop diuretics
Urine Ca decrease: thiazide (enhanced Ca reabsorption at DCT)