Unit 3- Adrenergic Antagonists Flashcards
Prazosin Selectivity
α1
Phenoxybenzamine Selectivity
α1
Phentolamine Selectivity
α
Antipemezole Selectivity
α2
Yohimbine Selectivity
α2
Carvedilol Selectivity
β>α1
Propanolol Selectivity
β
Timolol Selectivity
β
Metoprolol Selectivity
β1
α Antagonist Structure
Diverse, competitive antagonists
Phenothiazine Tranquilizers
α antagonists blocking receptors, causing decrease in peripheral vascular resistance
α Antagonist Cardiovascular
Dilate vessels
EPI Reversal Effect
Pretreating with α1 antagonists to reduce peripheral vascular resistance due to EPI
α1 Antagonist Effects
Decrease resistance to urine flow
α2 Antagonist Effects
Antiplatelet aggregation, stimulate insulin, reverse sedation
α Antagonist Effects
3rd eyelid protrusion, miosis, nasal stuffiness
Nonselective α Antagonists
Phenoxybenzamine, phenothiazine tranquilizers, and trazodone
Phenoxybenzamine
Irreversibly blocks α receptor to inhibit NE reuptake, antagonizes histamine, Ach, and serotonin receptors, manages catecholamine excess
Selective α1 Antagonists
Prazosin, tamsulosin, silodosin
Prazosin
Vessel dilation, decrease urine flow, reduces urethral pressure, decreases MAP