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DRUG

MECHANISM OF ACTION

ADVERSE EFFECTS

CAUTION

DIURETICS

Thiazides (HCTZ)

Loop diuretics (Lasix) useful if Cr. > 1.7

K+ Sparing diuretics Aldosterone blocker (Spironolactone)

Block Na, Cl reabsorption in the early convoluting tubule. Volume reduction leads to ( PVR

Block Na reabsorption at the ascending limb of Henle’s loop. By blocking solute reabsorption, passive reabsorption of water is prevented producing profound diuresis

Block the action of aldosterone in the distal nephron. K+ is retained while Na is excreted producing very mild diuresis

Hypotension, hypokalemia, hypochloremia, dehydration,

( LDL, ( glucose, ( uric acid

Hypotension, hypokalemia, hypochloremia, dehydration, ototoxicity,( LDL, ( HDL,

( glucose, ( uric acid

Hyperkalemia, endocrine effects

Pregnancy, gout, sulfa allergy, diabetes

Pregnancy, gout, diabetes. Caution with digoxin

Don’t combine with ACEI or in patients with renal insufficiency.

BETA ANDRENERGIC ANTAGONISTS

(BETA BLOCKERS)

Propran olol

Block the beta1 receptors in the heart which slows the heart rate, ( CO, ( AV conduction. ( renin production in the kidneys, ( PVR. Decreases mortality in patients with MI. Used to treat heart failure (Carvedilol-metoprolol), angina, dysrhythmias

Bradycardia, heart block, ( CO, bronchoconstriction, fatigue, insomnia, depression, sexual dysfunction, masks the s/s of hypoglycemia, inhibits glycogenolysis. Cardioselective have less AE (Metoprolol)

Caution in patients with heart block, bradycardia, heart failure, diabetes, asthma, depression, peripheral vascular disease, severe allergy. Abrupt withdrawal can lead to rebound tachycardia. Used with CCB(cardio suppression

ACE INHIBITORS

(ACEI)

Enala pril

Inhibits ACE which converts angiotensin I into angiotensin II. ( Production of angiotensin II (a potent vasoconstrictor) & aldosterone is reduced. Blood volume is decreased and arterioles and veins dilate to decrease BP. Used for heart failure. Dilates efferent arteriole in kidneys to decrease nephropathy. Prevents MI, stroke and death.

Hypotension, cough, angioedema, hyperkalemia, fetal injury, renal failure

Contraindicated in pregnancy or and in patients with renal artery stenosis or in patients with history of angioedema. Don’t use with K+ sparing diuretics. Use first line in diabetics for renal protection

ANGIOTENSIN RECEPTOR BLOCKERS

(ARBs)

Cande sartan

Blocks the action of angiotensin II. Overall affect same as with ACEI. Nephropathy is reduced. Prevents MI, stroke and death similar to ACEI

Hypotension, angioedema, hyperkalemia, fetal injury, renal failure. (no cough)

Contraindicated in pregnancy or in patients with renal artery stenosis or in patients with history of angioedema

CALCIUM CHANNEL BLOCKERS

(CCBs)

Amlo dipine

Non dihydropyridines- verapamil & diltiazem: Blocks calcium channels in the heart and blood vessels. Peripheral dilation of arterioles decreases BP. Blockage of calcium channels in heart ( coronary perfusion. Blockage at the and SA and AV node ( heart rate. Blockage in the myocardium ( force of contraction. Used for HTN and angina, dysrhythmias

Dyhydopyridines (Norvasc): Blocks calcium channels in arterioles which leads to vasodilation and ( BP. Blocks calcium channels mainly on vascular smooth muscle with minimal blockade of calcium channels in the heart.

Constipation, bradycardia, heart block, worsening of heart failure

Peripheral edema, hypotension, headache. Reflex tachycardia with nifedipine

Does not alter heart rate

Caution in heart failure, bradycardia, or if patient is on BB or digoxin

ALPHA 2 AGONISTS

(Clonidine )

Selective stimulation of alpha2 receptors in the CNS. Central activation of alpha2 receptors decreases sympathetic outflow to blood vessel and heart. Vasodilation and

( CO decreases blood pressure

Hypotension, bradycardia, ( CO, sedation, dry mouth, fetal harm, impotence, gynecomastia, depression, fetal harm.

Clonidine not used in pregnancy

Abrupt withdrawal of clonidine can lead to rebound hypertension.

(Methyldopa is drug of choice in pregnancy)

ALPHA1 BLOCKERS

Pra zosin

Blocks alpha1 receptors in the arterioles and veins preventing vasoconstriction. Relaxes smooth muscle in the bladder neck and prostatic capsule to benefit men with BPH

Orthostatic hypotension, reflex tachycardia, nasal congestion, inhibition of ejaculation

May increase cardiovascular events and heart failure. Not used first line to treat HTN

VASODILATORS

Hydralazine dilates arterioles. Used for eclampsia. Nipride dilates veins and arterioles. Organic nitrates dilate veins

Postural hypotension, reflex tachycardia, expansion of blood volume. Thiocyanate toxicity

ADRENERGIC NEURON-BLOCKING AGENTS

Reserpine causes depletion of NE from postganglionic sympathetic neurons to decrease stimulation of adrenergic receptors. ( activation of beta receptors slows heart rate and reduces cardiac output. ( alpha activation promotes vasodilation

Depression, bradycardia, orthostatic hypotension, nasal congestion