2nd line treatment of HTN
HF
G: orthostatic Hypotension
Ischemic Heart Disease
C: sedation, depression, reound HTN
R: can cause depression because can cross BBB
GUANETHIDINE, RESERPINE
M: sedation, lassitude, hepatotoxicity, hemolytic anemia
P: alpha-1 specific blocker [alpha-1 receptor blockade causes relax. of smooth muscle & decr. vasc. resist.) **Substantial 1st pass effects, still useful orally w/adjusted dose.
Cardiac Arrythymias
alpha-2 agonists @ central receptors, decr. vasc. resist., decr. C.O., decr. sympathetic output
Essential HTN
Centrally Acting Sympatholytics
Andrenergic Antagonists: alpha-blockers
Cannot use w/Sympathomimetics OTC (cold meds.=decongestants). Activate sensitive alpha-receptors. Trycyclic antidepressants prevent uptake of G. into neurons.
PRAZOSIN
competitive inhibition of beta-receptors, decr. C.O., & decr. vasc. resist. **1st pass effect
Peripherally Acting Sympatholytics
affects postgang. neurons of PSNS. [G: displace. of norepi. from granules & inhibit. of release of norepi.] & [R: depletion of catecholamines from granules]
P: first dose response (severe hypotension in response to 1st dose), depression, fatigue, fluid retention
treat essential HTN
treat HTN
Andrenergic Antagonists: beta-blockers (class II antidysrhythymic)
CLONIDINE, METHYLDOPA