Adrenergic Blockers Flashcards
What type of drug can be used in the treatment of Pheochromocytoma?
Name 2 drugs.
A nonselective Alpha blocker
Phentolamine, competitive inhibitor
(Think phatom of the opera, reversible binding)
Phenoxybenzamine, non competitive inhibition
(Think irreversable tattoo of Phoenix on phatom)
What are the major uses for alpha receptor antagonists ?
- Hypertension
- Pheochromocytoma (nonselective alpha blocker)
- Benign prostatic hyperplasia (selective alpha 1 blocker)
Name at least 3 selective alpha 1 blockers.
Prazosin
Doxazosin
Terazosin
…for BPH and HTN
Tamsulosin -blocks a subtype of alpha1 receptor called alpha 1a ;found in prostate; used for BPH
auf Deutsch: benigne prostatahyperplasie
Name 2 combined alpha-1 and beta blocking agents.
Labetalol (use in hypertensive emergencies)
carvedilol (use in CHF)
What is the advantage of selective alpha-1 antagonists over non-selective alpha blockers?
Selective alpha-1 antagonists cause less tachycardia
Name 3 types of drugs with ALPHA blocking side effects.
1) several (mostly tricyclics) antidepressants
E.g amitriptyline , imipramine
- they block norepinephrine re-uptake NET and dopamine re-uptake DAT
2) several antipsychotics
E.g phenolthiazides - chlorpromazine
may cause hypotension and reflex tachycardia
3) quinidine
Anti-arrhythmic drug, too rapid i.v injection, may cause blood pressure fall
In which condition is Esmolol used mostly?
Supra-ventricular tachycardia
Esmolol is a cardio selective beta blocker & Class II anti-arrhythmic drug !
It has the shortest half life among beta blockers (9min)
Mostly used in acute SVTs, also aortic dissection
Name a d.o.c used in case of hypertension associated with benign prostatic hyperplasia?
Doxazosin (selective alpha-1 blocker)
others include : prazosin, terazosin, tamsulosin (specific for BPH, little to no effect on BP)