Cardiac Pharmacology Update

 Common
Cardiac Medications by
› Examples
› Mechanism of Action (MOA)
› Side Effects
 Common Interactions
 Questions
› Enalapril (Vasotec), Lisinopril (Prinivil/Zestril), Captopril
(Capoten), Benazepril (Lotensin), Fosinopril
(Monopril), Quinapril (Accupril), Ramipril (Altace)
 MOA:
› suppresses the renin-angiotensin-aldosterone system;
prevention of the conversion of Angiotensin I (AT I) to
Angiotensin II (AT II, which is a vasoconstrictor)
 Vasodilation (↓ afterload, ↓ BP);
 Prevents cardiac remodeling after MI (prevent
development heart failure); Renal protective in DM
 Side Effects:
› ↓BP, ↑ K+, Cough, Angioedema, ↑ SCr & BUN,
neutropenia, hepatotoxicity; teratogenic
› Candesartan (Atacand), Irbesartan (Avapro),
Losartan (Cozaar), Olmesartan (Benicar),
Telmisartan (Micardis), Valsartan (Diovan)
› blocks Angtiotensin II, a vasoconstrictor, at the
receptor sites, effect similar to ACE I
› Vasodilation (↓ afterload, ↓ BP); Prevents cardiac
remodeling after MI (prevent development
heart failure); Renal protective in DM
Side Effects:
› ↓BP, ↑ K+, ↑ SCr & BUN, teratogenic
› Same as ACE-I, except w/o cough
› Selective BB
 Metoprolol (Lopressor/Toprol XL), Atenolol
(Tenormin), Betaxolol (Corgard), Bisoprolol
(Zebeta), Nebivolol (Bystolic)
› Non-Selective BB
 Propranolol (Inderal), Labetalol (Trandate),
Carvedilol (Coreg), Nadolol (Corgard)
MOA: ↓HR, ↓BP, and ↓ force of contraction
› Selective BB block the beta1 adrenergic
receptors of the heart—blocking of
› Non-Selective BB blocks both beta1 receptors
(heart) and beta2 receptors (bronchial and
vasculature sites)
 Side
› bradycardia, hypotension, masks
symptoms of hypoglycemia, fatigue,
lethargy, wheezing/dyspnea
nightmares, insomnia, impotence
 Non-Selective BB:
 Bronchospasm and vasoconstriction
 Use w/ caution in asthma, COPD, PVD,
› Non-Dihydropyridines—Verapamil
(Calan/Covera/Verelan/Isoptin), Diltiazem
› Dihydropyridines—Amlodipine (Norvasc),
Felodipine (Plendil), Isradipine (DynaCirc),
Nicardipine (Cardene), Nifedipine
(Procardia/Adalat), Nisoldipine (Sular)
MOA: ↓ HR, ↓ Contractility, vasodilation
› inhibits influx Ca+ into cardiac and vascular
smooth muscle cells
Side Effects:
› ↓ HR, ↓BP, edema, angioedema, gingival
hyperplasia, HA, flushing, dizziness
› Constipation (verapamil), CHF
exacerbation (verapamil/diltiazem), drug
interactions (verapamil/diltiazem)
› Increases force of heart contractions, ↓ HR
Side Effects:
› Manifestations of Toxicity:
 Anorexia, N/V/D, visual changes, arrhythmias
(PVCs), bradycardia
› Increased Risk of Toxicity:
 Renal impairment, low K+/Mg+, elderly,
hypothyroid; Drug interactions
• Examples:
 Loop—
 Furosemide (Lasix), Bumetanide (Bumex), Torsemide
(Demedex), Ethacryinic Acid
 Thiazide—
 Hydrochlorothiazide (HCTZ), Chlorthiazide (Diuril),
Chlorthalidone, Metolazone (Zaroxolyn)
 Potassium Sparing—
 Amiloride, Triamterene;
 Aldosterone Antagonists—
 Spironolatone (Aldactone), Eplerenone (Inspra)
• MOA: eliminates extracellular fluid
 Loop: inhibits Cl- reabsorption in loop of Henle
 Thiazide: inhibits reabsorption of Na+ and water,
 Potassium Sparing: inhibits K+ channels
 Aldosterone Antagonists: block aldosterone
 Loop:
 ↓K+, ↓Na+, ↓Ca+, ↓Mg+; Ototoxicity,
Photosensitivity, Dehydration
 Thiazide:
 ↓K+, ↓Na+, ↓Mg+; Hyperglycemia, ↑
Lipids, ↑Ca+, dehydration
 Triamterene/Amiloride:
 ↑ K+, GI upset, photosensitivity
 Spironolactone, etc.:
 ↑ K+, Gynecomastia, drowsiness, GI
Examples: Hydralazine, Minoxidil
 MOA:
› Relaxation smooth muscle, lowering pressure
needed to push blood through vessels
Side Effects:
› Hydralazine:
 Headache, drug fever, peripheral neuropathy, hepatitis,
skin reactions
› Minoxidil:
 Hair growth, fluid overload, use with BB to prevent reflex
› Nitroglycerin, Isosorbide Mononitrate (ISMO,
Monoket, Imdur), Isosorbide Dinitrate (Isordil)
› Relaxation of smooth muscle, lowering pressure
needed to push blood through vessels
Side Effects:
› Headache, flushing, hypotension, syncope,
cyanosis (blue) may indicate
› Alpha-1 Receptor Blocker—Doxazosin, Prazosin,
› Centrally Acting Agents—Clonidine, Methyldopa,
Guanabenz, Guanfacine
› Alpha-1 Receptor Blocker
 Peripheral relaxation of smooth muscle causing
› Centrally Acting Agents
 Stimulates alpha-2 adrenergic receptors in brain
causing a peripheral reduction in sympathetic
tone—↓ HR, ↓CO, ↓ peripheral resistance
 Side Effects
› Dizziness, drowsiness, syncope/hypotension,
depression, dry mouth, rebound HTN
› Aspirin, Clopidrogel (Plavix), Prasugrel
(Effient), Dipyridimole, Ticlodipine (Ticlid)
› Inhibits platelet aggregation and clot
Side Effects
› Bleeding
› GI upset, thrombocytopenia
Heparin, Enoxaparin (Lovenox), Dalteparin
 MOA—disruption of clotting cascade
(antithrombin III)
 Side Effects—bleeding, thrombocytopenia
Warfain (Coumadin)
 MOA—disruption of vitamin K dependent
clotting factors
 Side Effects—bleeding, skin necrosis
Statins (Atorvastatin, Fluvastatin, Lovastatin,
Pravastatin, Rosuvastatin, Simvastatin)
› MOA: blocks cholesterol synthesis and increases
› Side Effects: HA, GI upset, elev LFT’s, myopathy,
› **New FDA Warning not to exceed 40mg/day
Simvastatin unless previously stable on dose
without side effects. Do not increase patients
beyond 40mg.
Fibric Acid Analogs (Gemfibrozil, Fenofibrate)
› MOA: Decreases VLDL synthesis; increases
VLDL/Triglyceride removal
› Side Effects: elev LFT’s, myopathy, GI upset,
diarrhea, cholelithiasis, rash/itching
Cholesterol Absorption Inhibitor (Ezetimibe)
› Side Effects: headache, angioedema
Omega 3 Fatty Acids (Lovaza)
› Side Effects: halitosis, GI upset, weight gain,
prolonged bleeding time
› Side Effects: flushing, itching, GI upset,
hyperglycemia, elev LFT’s, elevated uric acid,
myopathy w/ high dose statins/fibrates
Bile Acid Sequestrants
› Side Effects: GI upset, bloating, constipation,
drug interactions (decreases absorption)
Class Ia Anti-Arrhythmic Agents
Depresses pacemaker rate, conduction and
› Quinidine
 Side Effects: syncope, TdP, ↓ BP, n/v/d, HA,
dizziness, tinitis, fever, thrombocytopenia
› Procainamide
 Side Effects: hypotension, TdP, SLE, n/v/d,
fever, rash, hepatitis, agranulocytosis, HA,
mood changes
Class Ib—Lidocaine
 Depresses abnormal cardiac activity, shortens
action potential duration, prolongs diastole
(extending time for recovery)
 Side Effects: Hypotension, parasthesias,
nausea, tremor, syncope, hearing
disturbances, slurred speech, seizures
Class Ic—Propafenone
 Similar to Quinidine, weak BB
 Side Effects: metalic taste, proarrhythmias
Class II—Beta-Blockers
Class III
› Amiodarone
 Broad spectrum of activity: lengthens action
potential, weak CCB, non-competitive BB,
alpha-receptor blocker
 Effects: vasodilatation, bradycardia, heart
block, TdP, pulmonary fibrosis, corneal
deposits, visual disturbances, sun sensitivity, skin
discoloration, constipation, hepatic
dysfunction, ataxia, HA, tremor, drug
• Class III, cont.
› Dronedarone
 Similar to amiodarone
 Effects: bradycardia, TdP, GI upset, weakness,
rash, liver injury, hepatic failure; new agent
› Sotolol
 Non-selective BB, prolongs action potential
 Side Effects: fatigue, bradycardia, dizziness,
dyspnea, proarrhythmias
Class IV—CCBs (Verapamil/Diltiazem)
› Drugs affecting Absorption
 Antibiotics alter GI Flora, affecting Warfarin
› Drugs affecting Protein Binding
› Drugs affecting Metabolism
 Increases Metabolism of Medication
 Rifampin ↑ warfarin metabolism, decreasing INR
 Decreases Metabolism of Medication
 Amiodarone inhibits hepatic enzymes from
metabolizing key medications
› Drugs affecting Excretion
 Amiodarone decreases digoxin clearance
Cialis/Viagra/Levitra potentiate
Nitrates/Vasodilators = Hypotension!
› Important to know if patients are taking
these medications
› “the biggies”
 Amiodarone
 Sulfamethoxazole (Septra/Bactrim)
 Metronidazole (Flagyl)
 Quinolones (Cipro, etc)
 Rifampin
Effect on PT/INR Mechanism
Estrogens, Vitamin K
Methimazole, Propylthiouracil
Barbituates, carbamazepine, chronic ETOH,
dicloxacillin, nafcillin, rifampin, phenytoin
Increased synthesis of clotting factors
Reduced catabolism of clotting
Increased warfarin metabolism
cholestyramine, colestipol, sucralfate
azathioprine, cyclophosphamide, cyclosporine,
Reduced warfarin absorption
thyroid hormones
cetotetan, vitamin E
Broad spectrum antibiotics
acute ETOH, allopurinol, amiodarone, azithromycin,
ciprofloxacin, erythromycin, clarithromycin,
fluconazole, fluorouracil, fluoxetine, ketoconazole,
metronidazole, omeprazole, phenytoin,
sulfamethoxazole, propafenone
acetaminophen, androgens, vitamin C, clofibrate,
corticosteroids, gemfibrozil, statins
Increased catabolism of clotting
Decreased synthesis of clotting
Impaired Vitamin K production by GI
Decreased warfarin metabolism
aspirin, clopidrogel, NSAIDs, SSRIs, ticlodipine
Increased bleeding risk
› Can reduce the antihypertensive effect of
ACE-I or cause/worsen renal failure
Digoxin & Amiodarone
› May need less digoxin if on chronic
Drugs prolonging QT interval
› Can cause arrhythmia when combined with
other drugs prolonging QT interval
Anti-arrhythmic medications known to prolong QT
› Amiodarone
› Dofetilide
› Procainamide
› Quinidine
 Other medications with potential to prolong QT Interval
› Droperidol
› Erythromycin
› Clarithromycin
› Haloperidol
› Methadone
› Ziprasidone
› Many others…

similar documents