Sympatholytics Flashcards
What are the SYMPATHOLYTICS?
These are the
a2 agonists
a1 blockers
B blockers
These drugs cancel the sympathetic effect
What are the a2 agonists?
Clonidine
a-Methyldopa
Clonidine
Uses
SE
Uses:
Hypertensive Urgency, DOES NOT DECREASE RENAL FLOW
ADHD
severe pain, ethanol and opioid withdrawal
SE CNS depression Bradycardia HypOTN Respiratory depression Small Pupil Size
a-Methyldopa
Uses
SE
Uses
HTN in preggos
SE: Direct Coombs, hemolytic anemia, SLE syndrome
What are the nonselective a blockers?
Phenoxybenzamine (irreversible)
Phentolamine (reversible)
Phenoxybenzamine
Uses
SE
Uses
Pre-op for pheochromocytoma to prevent catecholamine crisis
SE
Orthostatic hypOtn, reflex tachy so use B blocker AFTER giving phenoxybenzamine
Irreversible a blocker
Phentolamine
Uses
SE
Give to a pt who is on an MAO who ate a tyramine containing food
Reversible a blocker
Phentolamine
Uses
SE
Give to a pt who is on an MAO who ate a tyramine containing food
Reversible a blocker
What are the a1 selective blockers?
Uses
SEs
They end in osin
Prazosin
Terazosin
Doxazosin
Tamsulosin
Urinary symptoms of BPH
PTSD (prazosin)
HTN (except Tamulosin)
SEs:
Orthostatic HypOtn with first dose, dizziness, HA
What is the only selective a2 blocker?
Mirtazapine
What is the only selective a2 blocker?
Mirtazapine
Used for Depression
Causes sedation
Increases serum cholesterol
Increase appetite
What is the only selective a2 blocker?
Mirtazapine
Used for Depression
Causes sedation
Increases serum cholesterol
Increase appetite
How do B Blockers relieve angina?
Decrease HR and contractility–>less O2 consumption
How do BB blockers work for MIs?
Which ones should be used?
Decrease mortality Use MCB Metoprolol Carvedilol (a1 blockade as well) Bisoprolol
How do BBs help SVT
Which ones to use?
Decrease AV conduction velocity
Class II anti arrhythmic
ME
Metoprolol
Esmolol
How do BBs help in HTN
Decrease CO
Decrease Renin Secretion (B1 block on JGA cells) no reflex tachy from depressed renin bc B is blocked at B1 in heart
How do BBs help in CHF
Slow progression of chronic failure
How do BBs help with glaucoma?
Decrease production of aqueous humor from ciliary epithelium
Which BB causes sedation and can be used for phobias?
How?
DDIs?
Propranolol
Sedative effect is via a decrease of NE on B1 receptors in brain
DDIs:
EtOH, antihistamines
Uses of BB?
Impotence Brady, AV Block, CHF CNS effects (seizures, sedation, sleep alterations) Dyslipidemia (metoprolol) Asthmatics & COPDers (exacerbation)
Avoid in cocaine users to avoid unopposed a1 vasoconstriction
What are the selective B1 blockers?
Selective B1 antagonists from A to M. Since no B2 these are safer for asthmatics
Acebutolol
Betaxolol
Esmolol
Metoprolol
What are the non-selective B blockers?
B1=B2
Nadolol
Pindolol (partial agonist)
Propranolol
Timolol
What are the nonselective a1 & B blockers?
Carvedilol and Labetalol
What is Nebivolol and what does it inhibit?
Combines B1 blocking in heart with B3 stimulation in vasculature (leads to increased NO synthase production–>vasodilation)
What is the significance of Pindolol?
Only B blocker that can vasodilate and bronchodilate
Partial agonist
What are the vasospastic disorders that are exacerbated by B blockers?
Raynauds & Printzmetal
blocking B2 so no vasodilation
Why are B blockers bad for diabetics?
During fasting, need Epi to act on B2 receptors to initiate gluconeogenesis and glycogenolysis. A BB will prevent this so they get hypoglycemia and won’t even know it…
What are two BB that don’t cause hyperlipidemia?
Partial agonists
Acebutolol
Pindolol
