α/β blockers Flashcards
α blockers - drugs (and characteristics)
- phenoxybenzamine (non-selective, irreversible)
- phentolamine (non-selective, reversible)
- prazosin (α1)
- terazosin (α1)
- doxazosin (α1)
- tamsulosin (α1)
- mirtazapine (α2)
non-selective α-blockers (and special characteristics) and side effects
- phenoxybenzamine (irreversible)
- phentolamine (reversible)
SE: 1. orthostatic hypertension 2. reflex tachycardia
phenoxybenzamine - clinical use
pheochromocytoma (used preoperatively), to prevent catecholamine (hypertensive) crisis
phentolamine - clinical use
give to patients on MAO inhibitors who eat tyramine-containing fods
a1 selecive blockers - drugs and clinical use
-OSIN
1. prazosin 2. terazosin 3. doxazosin 4. tamsulosin
clinical use: 1. BPH 2. PTSD (prazosin)
3. hypertension (except tasmulosin)
a1 selecive blockers - adverse effects
- 1st-dose orthostatic hypertension
- dizziness
- headache
a2 selecive blockers - drug and clinical use
drug: Mirtazapine
clinical use: depression
a2 selecive blockers - drug and adverse effects
drug: Mirtazapine
adverse effect: 1. sedation 2. increases Serum cholesterol 3. increases appetite
epinephrine vs epinephrine + a blockade according to HR
HR is more increased with the blocker:
only epinephrine: increased due to β1
epinephrine + a blockade: increased due to β1 + reflex
epinephrine vs epinephrine + a blockade according to BP
Systolic, MAP and diastolic pressures are lower with the blocker
that difference is due to Net pressor effect (without) and the depressor effect (with)
phenylephrine vs phenylephrine + a blockade according to BP
Lower with the blocker
phenylephrine vs phenylephrine + a blockade according to according to BP
Systolic, MAP and diastolic pressures are lower with the blocker
β-blockers
- acebutolol
- atenolol
- betaxolol
- carvedilol
- esmolol
- labetalol
- metoprolo;
- nadolol
- nebivolol
- pindolol
- propranolol
- timolol
- bisoprolol
- carteolol
β-blockers - clinical use
- angina pectoris
- MI
- SVT
- Hypertension
- HF
- glaucoma
- Variceal bleeding
β-blockers - angina pectoris
decreases HR, Contractility
–> decreases O2 consuption
β-blockers - MI
decreases mortality
β-blockers - SVT
metoprolol, esmolol –> decreases AV conduction veolocity (class II)
β-blockers - Hypertension
decreases cardiac output, decreases renin secretion (β1 receptor on JGA cells)
β-blockers - HF
bisoprolol, carvedilol, metoprolol –> decreases mortality
β-blockers - glaucoma
timolol –> decreases secretion of aqueous humor
β-blockers - variceal bleeding
nadolol, timolol –> decreases hepatic venous pressure gradient and portal hypertension
β-blockers - side effects
- erectile dysfunction
- cardiovascular adverse effects
- CNS adverse effects
- dyslipidemia (meotprolol)
- asthma/COPD exacerbations
β-blockers - cardiovascular adverse effects
- bradycardia
- AV block
- HF
β-blockers - CNS adverse effects
- seizures
- sedation
- sleep alternations
β - blockers with cocaine
use with cation in cocaine users due to risk of unopposed α-adrenergic receptor agonist activity
β - blockers in DM
despite theoritical concer of masking hypoglycemia in diabetics, benefits likely outweigh risks –> not contraindicated
β1 selective antagonists (β1>β2) - drugs
A-M (except the α β nonselective and carteolol) +NEBIVOLOL
- acebutalol (partial) 2. atenolol 3. betaxolol
- esmolol 5. metoprolol 6. NEBIVOLOL (β1 antagonist and β3 agonist)
β - non-selective antagonists (β1=β2) - drugs
N-Z (and carteolol) - EXCEPT NEBIVOLOL
nadolol, pindolol (partial), propranolol, timolol
AND CARTEOLOL
nonselective α and β antagonist
ending in -LOL (instated of -olol)
carvedilol
labetalol
Nebivodol mechanism of action
cardiac selective β1-adrenergic antagonist with stimulation of β3 receptors, which activate NO synthae in the vasculature
partial β2 agonists - selectivity
acebutalol (β1>β2)
pindolol (β1=β2)
