objective 2.2 (pt.2) (1) Flashcards
(idiopathic, primary)
90 to 95% of cases
essential hypertension
5 to 10% of cases
Most commonly result of pheochromocytoma, pre-eclampsia, renal artery disease, sleep apnea, thyroid disease, or parathyroid disease
secondary hypertension
BP above 180/120; a medical emergency
malignant hyertension
what are the categories of antihypertensive drugs?
Adrenergic drugs
Angiotensin-converting enzyme (ACE) inhibitors
Angiotensin II receptor blockers (ARBs)
Calcium channel blockers
Diuretics
Vasodilators
Direct renin inhibitors
what are the 5 subcategories of adrenergic drugs?
Adrenergic neuron blockers (central and peripheral)
α2-receptor agonists (central)
α1-receptor blockers (peripheral)
β-receptor blockers (peripheral)
Combo α1 and β receptor blockers (peripheral)
Examples: clonidine and methyldopa
Not typically prescribed as first-line antihypertensive drugs
High incidence of unwanted adverse effects: orthostatic hypotension, fatigue, and dizziness
Adjunct drugs to treat hypertension after other drugs have failed
Used in conjunction with other antihypertensives such as diuretics
Α2 adrenergic receptor stimulators (agonists)
such as doxazosin, prazosin, and terazosin:
Lowering of BP occurs through dilation of arteries (in the periphery)
Peripherally acting α1 blockers
Commonly used α1 blocker
Reduces peripheral vascular resistance and BP by dilating both arteries and veins
Doxazosin mesylate (cardura)
Lowers BP through vasodilation
Prazosin hydrochloride (minipress)
Stimulate α2 adrenergic receptors in the brain and reduces SNS stimulation from the CNS
By decreasing SNS output, HR is slowed, and fource of contraction is lessened which lowers BP
Also affects the kidneys by reducing renin activity and the vasoconstriction associated with it
Centrally acting α2 adrenergic stimulators (agonists)
such as propranolol, metoprolol, and atenolol also work in the heart and vessels
These drugs decrease BP through reduction of HR
Reduction of the heart rate through β receptor blockade
Cause reduced secretion of renin
Long-term use causes reduce peripheral vascular resistance
βeta blockers
what are the indications of adrenergic drugs?
All used to treat hypertension
Glaucoma
BPH: doxazosin, prazosin, and terazosin
Management of severe HF when used with cardiac glycosides and diuretics
Clonidine is also used for menopausal flushing
what are the AE of adrenergic drugs?
High incidence or orthostatic hypotension
Most common: bradycardia with reflex tachycardia, dry mouth, drowsiness, sedation, constipation, depression, edema, sexual dysfunction, headaches, sleep disturbances, nausea, rash, cardiac disturbances, others
Lrg group of safe and effective drugs ie. enalapril and ramipril
Often used as first-line drugs for HF and hypertension
May be combined with thiazide diuretic or calcium channel blocker
angiotensin-converting enzyme (ACE) inhibitors
what are the MAO of ACE inhibitors?
Inhibits ACE, which is responsible for converting angiotensin I to angiotensin II
Angiotensin II is a potent vasoconstrictor
So by blocking angiotensin converting enzyme (ACE):
They prevent the formation of angiotensin II, this decreases the vascular constriction therefore causing BV dilation
This dilation of BV lowers BP
what are the indications of ACE inhibitors?
Hypertension: Bp: reduces BP by decreasing SVR
HF (drug used either alone or in combo with diuretics or other drugs)
Slow progression of left ventricular hypertrophy after MI
Renal protective effect in pts with diabetes
HTN and HF: prevent sodium and wtr reabsorption. Increases diuresis, decreases blood volume and HTN
Decreases preload therefore decreases work required of the heart
Cardioprotective:
Decreases SVR and preload, therefore decreases the work of the heart
Protects the heart from enlargement after an MI by decreasing the workload of the muscle
Drug of choice for hypertensive pts with HF
Reduce glomerular filtration pressure which protects the delicate structures of the kidneys
Cardiovascular drugs of choice for pts with diabetes bcuz of the renal protective effects
Standard therapy for diebetic pts to prevent the progression of diabetic nephropathy
renal protective effects
what are the AE of ACE inhibitors
Dry, nonproductive cough (ACE cough), which reverses when therapy is stopped
Fatigue, dizziness, headache, impaired taste
Mood changes
First-dose hypotensive effect
Possible hyperkalemia as ACE inhibitors can cause potassium to be retained
what are examples of ACE inhibitors?
Captopril, benazepril, enalapril, fosinopril sodium, lisinopril, cilazapril, perindopril, quinapril, ramipril, trandolapril
are inactive in their administered form and must be metabolized in their liver to an active form so as to be effective
prodrugs
what is the MOA of angiotensin II receptor blockers?
Also referred to as angiotensin II blockers
Affect primarily vascular smooth muscle and the adrenal glands
Selectively block the binding of angiotensin II to the receptors
Block vasoconstriction and the secretion of aldosterone
what are the indications of angiotensin II receptor blockers?
Hypertension
Adjunctive drugs for the treatment of HF
May be used alone or with other drugs such and diuretics
what are the AE of angiotensin II receptor blockers?
Upper respiratory infections and headaches most common
Dizziness, inability to sleep, diarrhea, dyspnea, heartburn, nasal congestion, back pain, fatigue, hyperkalemia is less likely to occur than with the ACE inhibitors
what are examples of angiotensin II receptor blockers?
Losartan, eprosartan mesylate, valsartan, candesartan cilexetil, aomesartan, telmisartan, azilsartan medonomil potassium
