8 Adrenergic Antagonists Flashcards
**a1 block **
predicted effect?
vasodilation
relaxatino fo iris radial muscle
relaxation of genitourinary muscle
viscous salivation decreased
a2 block
predicted effect?
increased NE release - sympathomimetic
increased insulin secretion
predicted effects of an a1, a2 block
acts as an a1 block
has increased b effects(due to NE release from a2 block)
a1/a2 non-selective antagonists
use?
phenoxybenzamine -irreversible
phenotolamine - competitive antagonist
used in catecholamine-secreting tumor surgeries
a1AR blockers/antagonists
prazosin
erazosin
tamsulosin
uses for a1 blockers
primary hypertension
raynaud’s disease
relaxing urinary tract sm
voiding kidney stones
a1a selective a1AR blocker used for benign prost. hypertrophy
tamsulosin
more selective relaxant of uretrhal sphincter
adverse effects of a1AR blockers
postural hypotension
nasal congestion
dry mouth
delayed ejaculation, retrograde ejactulation
priapism - sustained painful erection
a2AR blocker
use?
yohimbine
used for orthostatic hypotension
yohimbine adverse effects
palpitation
diarrhea
dyspepsia
indications for b-blocker
- CV issues: angina, arrhythmias, systolic heart failue, primary hypertension
- hyperthyroidism
- migraine
- glaucoma
- tremors, stagefright
adverse effects of b-blockers
- reduced exercise capacity
- AV conduction block
- peripheral vasoconstriction(cold extremities)
- withdrawal b-supersensitivity
- exercise induced hyperkalemia/muscle weakness
nonselective b-blockers
1st gen
propanolol - highly lipid soluble
timolol - eye drops
block b1/b2
b1 selective blockers
atenolol - longer t12/
metoprolol - moderate lipid solubility
nonselective b-blockers w/vasodilator action
3rd generation
carvedilol - moderate lipid solulibitly, longer t1/2
labetalol - a1 blocker as well as b-blocker