Hypertensive drugs

Question 1

Eplerenone (Inspra)

Answer 1

Class: Potassium-sparing diuretic
Mech: Block alodesterone; inhibits sodium reabsorption in distal tubule
Thera: Reduction in CHF mortality (30% in NYHA class III and IV); combination with other diuretics to prevent hypokalemia; edema; primary and secondary aldosteronism; hypertension; anti-testosterone agent
Important SE’s: Hyperkalemia; much lower incidence of gynecomastia and mennorhagia
Misc: Caution in renal failure, ACEi or ARB use, and in diabetics

Question 2

Captopril (Capoten)

Answer 2

Class: short-acting ACE-I (vasodilators)
Mech: Blocks endothelial ACE from converting angiotensin I to angiotensin II (potent vasoconstrictor); as a side effect, also prevents breakdown of bradykinin (potent vasodilator)
Thera: CHF, left ventricular hypertrophy, post-MI (prevents left ventricular remodeling)
Important SE’s: Dry cough, angioedema, inhibits renal autoregulation, hypotension
Misc: Short-acting; contraindicated in pregnancy, renal artery stenosis, hyperkalemia, and prior angioedema (no ARB allowed, either); caution in renal failure; reduces incidence of future CAD events, may reduce risk of diabetes

Question 3

Lisinopril (Prinivil); Benazepril (Lotensin); Quinapril (Accupril); Ramipril (Altace)

Answer 3

Class: long-acting ACE-I (vasodilators)
Mech: Blocks endothelial ACE from converting angiotensin I to angiotensin II (potent vasoconstrictor); as a side effect, also prevents breakdown of bradykinin (potent vasodilator)
Thera: CHF, left ventricular hypertrophy, post-MI (prevents left ventricular remodeling)
Important SEs: Dry cough, angioedema, decreased renal function, hypotension
Misc: Long-acting; contraindicated in pregnancy, renal artery stenosis, hyperkalemia, and prior angioedema (no ARB allowed, either); caution in renal failure; reduces incidence of future CAD events; may reduce risk of diabetes

Question 4

Enalapril (Vasotec)

Answer 4

Class: ACE-I (vasodilators)
Mech: Blocks endothelial ACE from converting angiotensin I to angiotensin II (potent vasoconstrictor); as a side effect, also prevents breakdown of bradykinin (potent vasodilator)
Thera: CHF, left ventricular hypertrophy, post-MI (prevents left ventricular remodeling)
Important SE’s: Dry cough, angioedema, decreased renal function, hypotension
Misc: Metabolized to enalaprilat, a more active metabolite;contraindicated in pregnancy, renal artery stenosis, hyperkalemia, and prior angioedema (no ARB allowed, either); caution in renal failure; reduces incidence of future CAD events; may reduce risk of diabetes

Question 5

Losartan (Cozaar); Valsartan (Diovan); Irbesartan (Avapro)

Answer 5

Class: Angiotensin II Recepter Blockers
Mech: Competitive inhibition of angiotensin II in vascular endothelium
Thera: Fall in peripheral vascular resistance, w/little change in HR or CO; same uses as ACE-I
Important SE’s: Angioedema, decreased renal function, hypotension; dry cough less frequent than with ACE-I
Misc: Contraindicated in pregnancy, renal artery stenosis, hyperkalemia, and prior angioedema (no ARB allowed, either); caution in renal failure

Question 6

Aliskiren (Tekturna)

Answer 6

Class: Renin inhibitor
Mech: Renin inhibitor
Thera: Not very effective

Question 7

Diltiazem (Cardizem); Verapamil (Calan)

Answer 7

Class: Non-dihydropyridine Calcium channel blockers
Mech: Interact with L-type voltage gated plasma membrane Ca channel –> decreased calcium entry into vascular smooth muscle cell, preventing contraction; causes decreased contractility, firing rate of aberrant pacemaker sites, and conduction velocity; prolongs repolarization in SA node and AV node (–> decreases HR); less vasodilation
Thera: Hypertension, anti-anginal (chronotropic effects –> decreased myocardial oxygen demand), SVT (class IV anti-arrhythymic)
Important SE’s: Leg edema, bradycardia, AV nodal blockade, hypotension, worsening heart failure
Other SE’s: Constipation (most common), headache, flushing
Misc: Contraindicated in overt decompensated heart failure, bradycardia, sinus node dysfunction, high-degree AV block

Question 8

Amlodipine (Norvasc); Nifedipine (Procardia)

Answer 8

Class: Dihydropyridine Calcium channel blockers
Mech: Interact with L-type voltage gated plasma membrane Ca channel –> decreased calcium entry into vascular smooth muscle cell, preventing contraction; causes dilation of epicardial coronary arteries, arteriolar resistance arteries; less heart-specific activity
Thera: Hypertension, Raynauds, angina (3rd choice drug)
Important SE’s: Leg edema (less than 1st generation), heart failure, AV nodal blockade, reflex tachycardia (lipophilic agents gain entry to brain and depress vasomotor center, rapidly dropping BP; this causes more reflex sympathetic activation (leading to adverse CV effects); long-acting agents are less lipophilic, and will cause less sympathetic activation and initial fall in BP)
OtherSE’s: Constipation (most common), headache, flushing
Misc: Contraindicated in overt decompensated heart failure, bradycardia, sinus node dysfunction, high-degree AV block

Question 9

Propranolol (Inderal)

Answer 9

Class: Nonselective β-blocker
Mech: Nonselective β-blocker; primarily reduces cardiac output
Important SE’s: Bronchospasm, bradycardia (negative chronotrope), CHF (negative ionotrope), masking of hypoglycemia symptoms
Other SE’s: Decreased exercise capacity, depression (crosses BBB), worsening symptoms of peripheral vascular disease

Question 10

Metoprolol (Lopressor); Atenolol (Tenormin)

Answer 10

Class: β1-selective blocker
Mech: Moderately selective β1 blockade
Other SE’s: Less likely to have bronchospasm, hypoglycemic awareness, and depression

Question 11

Bisoprolol (Zebeta); Nadolol (Corgard)

Answer 11

Class: β1-selective blocker
Mech: Moderately selective β1 blockade
Other SE’s: Less likely to have bronchospasm, hypoglycemic awareness, and depression
Misc: Longer-acting than other beta-blockers

Question 12

Labetolol (Trandate)

Answer 12

Class: Combined αβ blocker
Mech: β1 blockade with vasodilatory effects
Thera: Hypertensive urgency

Question 13

Carvedilol (Coreg)

Answer 13

Class: Combined αβ blocker
Mech: β1 blockade with vasodilatory effects
Thera: Acute coronary syndrome, CHF

Question 14

Esmolol (Brevibloc)

Answer 14

Class: β1-selective blocker
Thera: AV nodal blockade in unstable patients
Misc: Short half-life

Question 15

Terazosin (Hytrin); Doxazosin (Cardura)

Answer 15

Class: α1-adrenergic receptor antagonist
Mech: Blocks post-synaptic α1-adrenergic receptor antagonist on vascular smooth muscle
Thera: BPH; second-tier meds (use when other condition around, not for isolated hypertension)
Important SE’s: Orthostatic hypotension, fluid retention, worsening angina (secondary to reflex tachycardia)

Question 16

Clonidine (Catapres)

Answer 16

Class: Central α2-agonist
Mech: Stimulation of central α2a adrenergic receptors –> reduction in sympathetic outflow from vasomotor systems in brainstem; inhibition of renin release (secondary to decreased sympathetic tone)
Important SE’s: Rebound HTN if abruptly stopped; moderate orthostatic hypotension
Other Se’s: Sedation, dry mouth, fatigue, depression

Question 17

α-methyldopa (Aldomet)

Answer 17

Class: Central α2-agonist
Mech: Stimulation of central α2a adrenergic receptors –> reduction in sympathetic outflow from vasomotor systems in brainstem; inhibition of renin release (secondary to decreased sympathetic tone)
Thera: Hypertension of pregnancy (only)
Important SE’s: Rebound HTN if abruptly stopped; moderate orthostatic hypotension
Other SE’s: Sedation, dry mouth, fatigue, depression
Misc: Takes place of dopa, so less NE (also, methyl-NE activates α2)

Question 18

Reserpine (Serpalan)

Answer 18

Class: Ganglion blocking agent (adrenergic neuron blocking agent)
Mech: Blocks transport of NE, DA, and 5HIAA into storage granules in PNS and CNS –> less neurotransmitter available when nerves are stimulated
Thera: Decrease cardiac output and systemic vascular resistance
Important SE’s: Sedation, mental depression, Parkinsonism symptoms

Question 19

Hydralazine (Apresoline)

Answer 19

Class: Direct (vasodilators)
Mech: Relax smooth muscle of peripheral arterioles
Thera: Hypertensive urgency; patients with BOTH advanced CHF and hypertension
Important SE’s: Drug-induced lupus
Other SE’s; reflex tachycardia
Misc: Serves as an antioxidant, preventing oxidation of NO

Question 20

Minoxidil (Loniten)

Answer 20

Class: Direct (vasodilators)
Mech: Relax smooth muscle of peripheral arterioles
Thera: Refractory hypertension; hair loss
Important SE’s: Pericardial effusion; hirsutism
Other SE’s: reflex tachycardia
Misc: Smooth muscle relaxation by opening cardiovascular ATP-sensitive potassium channels