Adrenergic Antagonists - Drug Flashcards
What are the classes of adrenergic antagonist
Alpha and beta blocker
Alpha receptor blocker
Beta blocker
Alpha blocker types?
- alpha1 selective , alpha2 selective and non selective blockers
What are the two main non selective alpha blocker
- phenoxybenzamine
- phetolamine
Uses of phenoxybezamine
Pheochromocytoma (DOC)
Antidote of cocaine, amphetatime
Raynaud’s dx
Automatic dysreflexia
S/e is phenoxybenzamine
Reflex tachycardia
Orthostatic Hypotension
Stuffy nose
Sexual dysfunction: ejaculation
Is pheoxy benzamine a reversible or irreversible blocker
Irreversible blocker
Phentolamine is a _________ blocker
Reversible non selective adrenergic blocker with a short half life.
Used for short term management of phecromocytoma, tx of impotence (rarely used)
Examples of A1 selective blocker
‘osins’
Note that doxaosin is long acting
Uses of A1 selective blocker
BPH (DOC) :tamsulosin
PTSD: Prazosin
Urinary hesitancy
HTN: all except tamsulosin
Side effects of selective alpha blocker
Headache dizziness fatigue First dose syncope Reflex tachycardia Orthostatic hypotension NASAL stuffiness Ejaculation problem
Tx of bph
Tamsulosin selective A1 blocker
Different A1 receptors
A1 a : urethra, urinary bladder, prostrate A1b: blood vessels, prostrate A1 c A1d urinary bladder A1e
Types of beta blocker
Selective and non selective
olols
NonSelective beta blocker
TPN
Timolol
Propanolol
Nadolol
Pindolol (non-selective)
Cardio selective b1 blocker
Acebutolol (partial agonist)
Metoprolol
Esmolol
Atenolol
MAE
What b blocker is given during emergency
Esmolol cardio selective
It has a short half life
Effects of non selective beta blocker in non diabetic pts
Type 2 dm due to insulin resistant
Effects of non selective beta blocker in diabetic pts
Hypoglycemia due to lowered glycogenolysis
Non selective beta blocker effect : LIPOLYSIS explain
No insulin so LPL Is not stimulated and can’t convert VLDL to ILDL
insulin is known to activate LPL in adipocytes and its placement in the capillary endothelium. By contrast, insulin has been shown to decrease expression of muscle LPL. Muscle and myocardial LPL is instead activated by glucagon and adrenaline.
Uses of bb
Angina (doc) HTN Arrhythmia Migraine Thyrotoxicosis Anxiety dx
Side effects of propranolol
Bronchconstriction Na retention Arrhythmia Sexual impairment Fasting hypoglycemia Fatigue and exercise intolerance (not caused by alpha blocker)
CNS effects cus it crosses bbb( atenolol doesn’t)
What beta blocker drugs are useful for the tx of glaucoma
Timolol
They prevent ne from binding to the B2 receptor so low camp and low aqueous humor formation
Tx of glaucoma
- epinephrine
- bb: Timolol
- pilocarpine
Beta1 selective blocker
Same effects as bb non selective but safe for cop dp d and asthma pts
Esmolol
Tx of acute supraventricular arrhythmia
Also with METOPROLOL (s/e- dyslipidemia)
How can bb mask insulin induced hypoglycemia
It suppresses cathecolamines and the normal symptoms of hypoglycemia is not seen ( tremors, sweating and palpitations)
Bb with intrinsic sympathomimmetic action
Pindolol
Acebutolol
Alpha and better blockers
Labetol
Carvidilol
Uses of A&B blocker
HTN in elderly black pt
Cocaine induced HTN
Pregnancy with HTN
S/e Orthostatic HTN and dizziness
Other uses of phenolamine
- second line drug for cocaine induced HTN
- given to pts on MAO inhibitors who take tyramine containing foods
- to treat NE extravasation
An example of an A2 selective blocker
Mirtazapine
Uses of mirtazapine
Depression
S/e of mirtazapine
Sedation
Increase serum cholesterol
Increase appetite
Symptomatic tx of hyperthyroidism
Propranolol
B blocker for variceal bleeding
Nadolol, propranolol, carvedilol
Nebivolol
A beta blocker which combines
cardiac selective B1 adrenergic blockage + B3
Cause increase of NO as it activates NO synthase in the blood vessel
