First Aid Autonomic/Cardiac Pharmacology Flashcards
Major functions of alpha1 q receptor
increase vascular SM contraction
increase pupillary dilator muscle contraction (mydriasis)
increase intestinal and bladder sphincter muscle contraction
Major functions of alpha2 i receptor
decrease sympathetic outflow decrease insulin release decrease lipolysis increase platelet aggregation decrease aqueous humor production
Major functions of beta1 s receptor
increase heart rate
increase contractility
increase renin release
increase lipolysis
Major functions of beta2 s receptor
vaodilation, bronchodilation increase lipolysis increase insulin release decrease uterine tone ciliary muscle relaxation increase aqueous humor production
Major functions of M1 q receptor
CNS
enteric nervous system
Major functions of M2 i receptor
decrease heart rate and contractility of atria
Major functions of M3 q receptor
increased exocrine gland secretions
increase gut peristalsis
increase bladder contraction
bronchoconstriction
increase pupillary sphincter muscle contraction
ciliary muscle contraction (accommodation)
Major function of D1 s receptor (dopamine)
relaxes renal vascular smooth muscle
Major function of D2 i receptor (dopamine)
modulates transmitter release especially in brain
Major function of H1 q receptor
increased nasal and bronchial mucus production
increased vascular permeability
contraction of bronchioles
pruritus, pain
Major function of H2 s receptor
increased gastric acid secretion
Major function of V1 q receptor (vasopressin)
increased vascular SM contraction
Major function of V2 s receptor (vasopressin)
increased H2O permeability and resorption in collecting tubules of kidney
Sympathetic receptors
alpha1
alpha2
beta1
beta2
Parasympathetic receptors
M1
M2
M3
Cholinomimetic agents/direct agonists
carbachol
methacholine
pilocarpine
bethanechol
Cholinomimetic agents/indirect agonists/anticholinesterases
Donepezil, galantamine, rivastigmine edrophonium neostigmine physostigmine pyridostigmine
Bethanechol
postoperative ileus, neurogenic ileus, urinary retention
Carbachol
constricts pupil and relieves intraocular pressure in glaucoma (carbon copy of acetylcholine)
Methacholine
challenge test for the diagnosis of asthma (stimulates muscarinic receptors in airway)
Pilocarpine
potent stimulator of sweat, tears and saliva
open angle and closed angle glaucoma
contracts ciliary muscle of eye; pupillary sphincter
resistant to AChE
Donepezil, galantamine, rivastigmine
Alzheimer disease
Edrophonium
Historically used for diagnosis of myasthenia gravis
Neostigmine
postoperative and neurogenic ileus and urinary retention
myasthenia gravis
reversal of neuromuscular junction blockade
Physostigmine
Anticholinergic toxicity; crosses BBB
Pyridostigmine
myasthenia gravis (long acting); does not penetrate BBB
Cholinesterase inhibitor poisoning often due to
organophosphates that irreversibly inhibit AChE
Cholinesterase inhibitor poisoning (insecticides etc)
DUMBBELSS: Diarrhea Urination Miosis Bronchospasm Bradycardia Excitation of skeletal muscle and CNS Lacrimation Sweating Saliva
Muscarinic antagonists
atropine, homatropine, tropicamide benztropine scopolamine ipratropium, tiotropium oxybutynin, darifenacin, and solifenacin glycopyrrolate
Atropine, homatropine, tropicamide
eye; produces mydriasis and cyloplegia
Benztropine
CNS; Parkinson disease
Scopolamine
CNS; Motion sickness
Ipratropium, triotropium
Respiratory; COPD, asthma
Oxybutynin, darifenacin, and solifenacin
tolterodine, fesoterodine, trospium
GU; reduce urgency in mild cystitis and reduce bladder spasms
Glycopyrrolate
GU, respiratory; parenteral: preoperative use to reduce airway secretions
oral: drooling, peptic ulders
Atropine
muscarinic antagonist; used to treat bradycardia and for ophthalmic application
Atropine is the antidote for
cholinesterase inhibitor poisoning
insecticides
Direct sympathomimetics
Epinephrine Norepinephrine Isoproterenol Dopamine Dobutamine Phenylephrine Albuterol, salmeterol, terbutaline
Indirect sympathomimetics
Amphetamine
Ephedrine
Cocaine
Epinephrine
beta > alpha
(alpha effects predominate at high doses)
anaphylaxis, open angle glaucoma, asthma, hypotension
Norepinephrine
alpha1 > alpha2 > beta1
hypotension (but decreases renal perfusion)
Isoproterenol
beta1 = beta2
electrophysiologic evaluation of tachyarrhythmias
can worsen ischemia
Dopamine
D1=D2 > beta > alpha
unstable bradycardia, heart failure, shock; inotropic and chronotropic alpha effects predominate at high doses
Dobutamine
beta1 > beta2, alpha heart failure (inotropic > chronotropic), cardiac stress testing
Phenylephrine
alpha1 > alpha2
hypotension (vasoconstrictor), ocular procedures (mydriatic), rhinitis (decongestant)
Albuterol, salmeterol, terbutaline
beta2 > beta1
albuterol for acute asthma; salmeterol for long-term asthma or COPD control; terbutaline to reduce premature uterine contractions
Amphetamine
indirect general agonist, reuptake inhibitor, also releases stored catecholamines
narcolepsy, obesity, ADD
Ephedrine
indirect general agonist, releases stored catecholamines
nasal decongestant, urinary incontinence, hypotension
Cocaine
indirect general agonist, reuptake inhibitor
causes vasoconstriction and local anesthesia
What would you never give if cocaine intoxication is suspected?
never give a beta-blocker if cocaine intoxication is suspected because it can lead to unopposed alpha1 activation and extreme hypertension
Sympatholytics (alpha2-agonists)
Clonidine
alpha-methyldopa
Clonidine
hypertensive urgency (limited); does not decrease renal blood flow ADHD, severe pain, and a variety of off-label indications (ethanol and opioid withdrawal)
alpha-methyldopa
hypertension in pregnancy
safe in pregnancy
Nonselective alpha-blockers
Phenoxybenzamine (irreversible)
Phentolamine (reversible)
alpha1 selective alpha-blockers
Prazosin
Terazosin
Doxazosin
Tamsulosin
alpha2 selective alpha-blocker
Mirtazapine
Phenoxybenzamine (irreversible)
Pheochromocytoma (used preoperatively) to prevent catecholamine (hypertensive) crisis
Phentolamine (reversible)
give to patients on MAO inhibitors who eat tyramine-containing foods
Prazosin, terazosin, doxazosin, tamsulosin
Urinary symptoms of BPH; PTSD (prazosin); hypertension (except tamsulosin)
Mirtazapine
Depression
beta-blockers
Metoprolol, acebutolol, betaxolol, carvedilol, esmolol, atenolol, nadolol, timolol, pindolol, labetalol
Application of beta-blockers
angina pectoris, MI, SVT (metoprolol, esmolol), hypertension, CHF, glaucoma (timolol)
Toxicity of beta blockers
impotence, CV adverse effects (bradycardia, AV block, CHF), CNS adverse effects (seizures, sedation), dyslipidemia (metoprolol), and asthmatic/COPD exacerbation
beta1-selective antagonists
acebutolol (partial agonist) atenolol betazolol esmolol metoprolol
Nonselective beta antagonists
nadolol
pindolol (partial agonist)
propranolol
timolol
Nonselective alpha and beta antagonists
carvedilol
labetalol
Nebivolol
combines cardiac-selective beta1-adrenergic blockade with stimulation of beta3 receptors, which activate nitric oxide synthase in the vasculature
Which drug class causes a dry cough?
ACE inhibitors
Primary (essential) hypertension treatment
diuretics
ACE inhibitors
angiotensin II receptor blockers (ARBs)
calcium channel blockers
Hypertension with CHF treatment
diuretics
ACEi/ARBs
beta-blockers (compensated CHF)
aldosterone antagonists
Hypertension with diabetes mellitus treatment
ACEi/ARBs calcium channel blockers diuretics beta-blockers alpha-blockers
Calcium channel blockers
Amlodipine, nimodipine, nifedipine (DHP); diltiazem, verapamil (non-DHP)
Mechanism of calcium channel blockers
block voltage-dependent L-type calcium channels of cardiac and smooth muscle, thereby reducing muscle contractility
Calcium channel blockers with vascular smooth muscle selectivity
amlodipine = nifedipine > diltiazem > verapamil
Calcium channel blockers with heart selectivity
verapamil > diltiazem > amlodipine = nifedipine
Clinical uses of DHP calcium channel blockers
(except nimodipine): hypertension, angina (including Prinzmeal), Raynaud phenomenon
Clinical uses of Non-DHP calcium channel blockers
hypertension, angina, Afib/Aflutter
Clinical uses of nimidipine
subarachnoid hemorrhage (prevents cerebral vasospasm)
Hydralazine mechanism
increases cGMP -> smooth muscle relaxation
vasodidlates arterioles > veins
afterload reduction
Clinical uses of hydralazine
severe hypertension, CHF
first-line therapy for hypertension in pregnancy with methyldopa
frequently coadministered with a beta-blockers to prevent reflex tachycardia
Toxicity of hydralazine
compensatory tachycardia (contraindicated in angina/CAD)
fluid retention, nausea, headache, angina
Lupus-like syndrome
Commonly used drugs in a hypertensive emergency
nitroprusside, nicardipine, clevidipine. labetalol, and fenoldopam
Nitroprusside
short actin, increases cGMP via direct release of NO
can cause cyanide toxicity
Nitroglycerin, isosorbide dinitrate mechanism
vasodilates by increasing NO in vascular smooth muscle -> increases in cGMP and smooth muscle relaxation
dilates veins»_space; arteries; decreases preload
Clinical use of nitroglycerin and isosorbide dinitrate
angina, acute coronary syndrome, pulmonary edema
Toxicity of nitroglycerin and isosorbide dinitrate
reflex tachycardia (treat with beta blockers) hypotension, flushing, headache, "Monday disease" in industrial exposure
Antianginal therapy
nitrates (affect preload)
beta-blockers (affect afterload)
Mechanism of cardiac glycosides
direct inhibition of Na+/K+ ATPase leads to indirect inhibition of Na+/Ca2+ exchanger
increase in Ca2+ -> positive inotropy
stimulates vagal nerve -> decreased heart rate
Name a cardiac glycoside
digoxin
Clinical use of digoxin/cardiac glycosides
CHF (increase contractility) atrial fibrillation (decrease conduction at AV node and depression of SA node)
