end Flashcards
Phenylalkylamine
Verapamil
Benzothiazepine
Diltiazem
1,4-Dihydropyridines
Nifedipine (prototype) Amlodipine (longest acting)
Use-dependent CCBs
Verapamil Diltiazem
Voltage-dependent CCBs
Nifedipine Amlodipine
What CCB do you use for Angina?
Diltiazem Because decreases SA node firing rate, reduces cardiac after load by vasodilation, also increases blood flow to myocardium to prevent ischemia Nifednipine and Amlodipine can also be used because they reduce myocardial oxygen demand and arterial pressure
What CCBs are used for Supraventricular arrhythmias?
Diltiazem or Verapamil Because they reduce the firing rate of the SA node and reduce conduction through AV node
Which CCBs are used to treat hypertension?
Usually Dihydropyridines Because of potent vasodilator effects BUT may trigger reflex tachycardia particularly with short acting Dihydropyridines
Diuretics, Vasodilators
Fenoldopam, Dopamine, Atriopeptins
What is the mechanism of action of the vasodilatory diuretics??
Increase RBF without decreasing GFR FF decreases (reduces protein conc and hydroosmotic forces in peritubular capillaries)– allow Na and H20 to leak back into the tubule This reduces net reabsorption so Na excretion increases Weak as diuretics due to compensatory Na reabsorption in more distal nephron segment
Osmotic diuretic Freely filterable at glomerulus Not reabsorbed Metabolically inert
Mannitol
What is the mechanism of action of osmotic diuretics??
Given intravenously Act in tubular lumen as non-reabsorbable solute Urine volume and sodium excretion are proportional to the osmotic load Increases the urinary excretion of sodium, potassium, chloride, water and mannitol
What are osmotic diuretics used for?
Edema Glaucoma-reduces intraocular pressure Acute renal failure
Carbonic Anhydrase Inhibitor Orally active Weak diuretics Inhibited by acidosis-limits clinical use
Acetazolamide
What is the mechanism of carbonic anhydrase inhibitors?
Filtered and secreted by the organic acid transporter (OAT) - acts from tubular lumen Inhibit carbonic anhydrase in the proximal and distal tubule Carbonic anhydrase provides hydrogen ions for bicarbonate reabsorption Increase the excretion of sodium, potassium, bicarbonate and water Alkalinize the urine
What are Carbonic Anhydrase inhibitors used for?
Glaucoma - reduced aqueous humor formation and intraocular pressure Alkalinize the urine – decrease drug toxicity Mountain or altitude sickness Anticonvulsant SE= Metabolic acidosis, hypokalemia
Loop Diuretics Rapid onset, short duration of action
Furosemide, Bumetanide, Ethacrynic Acid
What is the mechanism of Loop Diuretics??
Filtered and secreted by the OAT Inhibits Na-K-2Cl symporter Acts on cortical and medullary segments of the ascending limb of the loop of Henle Increase excretion of Na, K, Cl and H20
What are the Loop Diuretics used for?
Edema of cardiac, hepatic or renal origin Acute pulmonary edema HTN
Thiazide and Thiazide-Like Diuretics Moderate onset of activity Long duration of action
Hydrochlorothiazide Metolazone
What is the mechanism of action of Thiazide diuretics?
Filtered and secreted by the OAT Inhibits Na-Cl symporter Acts on cortical segment of distal tubule Increases excretion of Na, K, Cl and H20 Urine is hypertonic - unable to dilute
What are the Thiazide Diuretics used for?
Edema due to CHF HTN Hypercalemia/Ca salt-renal caliculi
K+ Sparring Diuretics, Aldosterone Antagonists
Spironolactone, Eplerenone
K+ Sparring Diuretics, Na+ channel inhibitors
Amiloride, Triamterene
What is the mechanism of action of the Potassium Sparring Diuretics?
Increase sodium excretion, reduce potassium excretion, Increase the urinary excretion of Na, Cl and H20
What are the Potassium Sparring Diuretics used for?
Edema HTN Usually used in combo with thiazide loop diuretic to enhance natriuresis without potassium loss
Catlyzes antithrombin inhibition of Xa and IIa (also IXa, XIa and XIIa)
Heparin
LMWH’s - catalyze antithrombin inhibition of Xa
Subcutaneous
Enoxaparin
Dalteparin
Direct Thrombin inhibitors
IV
Lepirudin
Bivalirudin
Prodrug, Oral
Direct thrombin inhibitor that inhibits fibrin-bound and free thrombin
Dabigatran
Reversible Xa inhibitor
Oral
Rivaroxaban
Direct factor Xa Inhibitor
IV
Fondaparinux
Heparin antagonist
Protamine sulfate
Inhibits VKORC
Competitive inhibitor of vitamin K –> inactivation of II, VII, IX, X
Warfarin
Binds fibrin
Activates fibrin-bound plasminogen –> plasmin = clot resolution
Tissue plasminogen activate (t-PA)
Alteplase
Procoagulant - potent inhibitor of fibrinolysis
Blocks binding of plasmin to fibrin
Aminocaproic Acid
Used as antiplatelet at low doses
Irreversible inhibitor of COX-1 in platelets
Inhibits platelet production of TXA2
Aspirin
Phosphodiesterase inhibition,
Increase cAMP, decrease platelet aggregation
Dipyridamole
Prodrugs
Act through P2Ya/P2Y12 receptors to inhibit G receptor activation
Increase cAMP
Ticlopidine
Clopidogrel
Prasugrel
Ticagrelor
Glycoprotein IIb/IIIa receptor blocker
Fab fragment monoclonal antibody
Prevents binding of fibrinogen, vWF and other adhesive molecules
IV
Abciximab
Glycoprotein IIb/IIIa receptor blocker
Cyclic heptapeptide
Block binding of fibrinogen activated platelets
IV
Eptifibatide
