Nephrology Flashcards
Which drug classes work on the glomerulus as their site of action?
None!
Which drug classes work on the proximal tubules?
- Carbonic anhydrase inhibitors (CAIs)
- Adenosine antagonist (current investigation)
Carbonic anhydrase inhibitors (CAIs) MOA
- Inhibits enzyme responsible for dehydration of H2CO3
- Reduces aqueous humor production
CAI examples
Acetazolamide
Dorzolamide (ophthalmic)
Brinzolamide (ophthalmic)
Indications for CAIs
- Glaucoma
- Urinary acidosis
- Metabolic alkalosis
- Acute mountain sickness
ADRs of CAIs
- Renal stones
- K wasting
- Drowsiness
- Hypersensitivity reaction
Contraindication of CAIs
Hepatic cirrhosis
PK of CAIs
- Absorbs well
- Increases urine pH
- Onset w/in 30 mins
- Duration 12 hrs
Which drug classes work on Loop of Henle?
Loop diuretics
Loop diuretic MOA
Inhibits Na/K/Cl transporter
Indications for loop diuretics
- Edema
- Hypercalcemia
- Hyperkalemia
- Anion overdose
ADRs of loop diuretics
- Low Mg
- High uric acid
- Ototoxicity
- Allergic reaction
Contraindications of loop diuretics
- Careful in hepatic cirrhosis, renal/heart failure
- Sulfa allergy
Drug-drug interactions of loop diuretics
NSAIDs can decrease effectiveness of loop diuretics
PO to IV conversion of furosemide
2:1
40 mg PO = 20 mg IV
PO to IV conversion of torsemide and bumetanide
1:1
Which drug classes work on distal convoluted tubule?
Thiazide diuretics
Thiazide MOA
- Inhibits NaCl transporter
- Enhances Ca reabsorption
Indications for thiazides
- HTN
- Heart failure
- Nephrogenic DI
- Nephrolithiasis
PK of thiazides
- Absorbed slowly
- Chlorthalidone slowest but longer duration of action
What agent is the slowest absorbed but longest lasting thiazide?
Chlorthalidone
ADRs of thiazides
- Low Na, K
- High uric acid, lipids
- Allergic rxn
- Photosensitivity
Thiazides should be used with caution in which conditions?
- Hepatic cirrhosis
- Renal failure
- Heart failure
Which thiazide is effective with GFR less than 20 ml/min?
Metolazone
Which thiazide comes in IV formulation?
Chlorothiazide
Which drug classes work on the cortical collecting tubule?
K sparing diuretics
Adenosine antagonists
Indications for K sparing diuretics
Hypokalemia (prevention/tx)
Indications for spironolactone
- Hyperaldosterism
- Polycystic ovary disease
- Hirsutism
ADRs of K sparing diuretics
- High K
- Kidney stones (triamterene)
- Gynecomastia, impotence (spironolactone)
When is spironolactone contraindicated?
Addison’s disease
Drug-drug interactions of K sparing diuretics
- Eplerenone only
- Strong CYP3A4 agents
Which drug classes act on the medullary collecting duct?
Vassopressin (ADH) antagonists
Indications of ADH antagonists
- Congestive heart failure
- SIADH
ADH antagonist agents (indirect)
Lithium
Demeclocycline
(MOA unknown)
ADH antagonist agents (direct)
Conivaptan
Tolvaptan
(MOA: inhibits vasopressin receptors)
ADRs of direct ADH antagonists
- Nausea
- Dry mouth
- Thirst
CI of direct ADH antagonists
- Hypovolemia
- Hyponatremia
Drug-drug interactions of direct ADH antagonists
Strong CYP3A4 agents
Osmotic diuretics MOA
- Increase osmotic pressure in glomerulus
- Decreases reabsorption of H2O and electrolytes
Indications for osmotic diuretics
- Cerebral edema
- Acute glaucoma
- Bronchial hyper-responsiveness
Osmotic diuretic agents
- Glycerol
- Mannitol (PO, inhaled, IV)
PK of osmotic diuretics
- Poorly absorbed
- Quickly excreted
ADRs of glycerol
N/V, diarrhea
ADRs of mannitol
Excessive volume expansion (heart failure, edema, pulm congestion)
How are osmotic agents better tolerated?
- Oral
- Mixed w/small amount of juice
- Add ice
- Small sips
How is CrCl calculated?
Cockroft-Gault (MC)
Which meds can cause vasoconstriction of afferent arteriole?
NSAIDs
Cyclosporine
Tacrolimus
Amphotericin B
Which meds can cause vasodilation of efferent arteriole?
ACEI/ARBs
Dilt and verapamil
Which meds cause direct toxicity to renal tubules?
Aminoglycosides
Amphotericin B
Cisplatin and carboplatin
Radiocontrast agents
What drug has been proven to accelerate the recovery of renal failure?
None!
