Learning objectives
Upon completion of this chapter, you should be able to:
1.
Outline the normal controls of blood pressure and explain how the various drugs used to treat hypertension
or hypotension affect these controls.
2.
Describe the therapeutic actions, indications, pharmacokinetics, contraindications, most common adverse
reactions and important drug–drug interactions associated with drugs affecting blood pressure.
3.
Discuss the use of drugs that affect blood pressure across the lifespan.
4.
Compare and contrast the drugs captopril, losartan, diltiazem, nitroprusside and midodrine with other agents
in their class and with other agents used to affect blood pressure.
5.
Outline the care considerations, including important teaching points, for people receiving drugs used to
affect blood pressure.
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Drugs affecting
blood pressure
Glossary of key terms
angiotensin-converting-enzyme (ACE) inhibitor:
drug that blocks ACE, the enzyme responsible for converting angiotensin I to
angiotensin II in the lungs; this blockage prevents the vasoconstriction and aldosterone release related to angiotensin II
angiotensin II receptors:
specific receptors found in blood vessels and in the adrenal gland that react with angiotensin II to cause
vasoconstriction and release of aldosterone
baroreceptor:
pressure receptor; located in the arch of the aorta and in the carotid artery; responds to changes in pressure and
influences the medulla to stimulate the sympathetic system to increase or decrease blood pressure
cardiovascular centre:
area of the medulla at which stimulation will activate the sympathetic nervous system to increase blood
pressure, heart rate and so forth
essential hypertension:
sustained blood pressure above normal limits with no discernible underlying cause
hypotension:
sustained blood pressure that is lower than that required to adequately perfuse all of the body’s tissues
peripheral resistance:
force that resists the flow of blood through the vessels, mostly determined by the arterioles, which contract to
increase resistance; important in determining overall blood pressure
renin–angiotensin–aldosterone system:
compensatory process that leads to increased blood pressure and blood volume to ensure
perfusion of the kidneys; important in the continual regulation of blood pressure
shock:
severe hypotension that can lead to accumulation of waste products and cell death
stroke volume:
the amount of blood pumped out of the ventricle with each beat; important in determining blood pressure
Test your current knowledge of drugs affecting blood pressure with a PrepU Practice Quiz!
ANTIHYPERTENSIVE AGENTS
Angiotensin-converting-
enzyme inhibitors
captopril
enalapril
fosinopril
lisinopril
perindopril
quinapril
ramipril
trandolapril
Angiotensin II–receptor
blockers
candesartan
eprosartan
irbesartan
losartan
olmesartan
telmisartan
valsartan
Calcium channel blockers
amlodipine
diltiazem
felodipine
isradipine
lercanidipine
nifedipine
verapamil
Vasodilators
diazoxide
hydralazine
minoxidil
sodium nitroprusside
