Pharm Basics Flashcards
Cholinomimetic agents: direct agonists
Bethanechol, carbachol, methacholine, pilocarpine
Cholinomimetic agents: indirect agonists (acetylcholinesterase inhibitors)
galantamine, donepezil, rivastigmine, edrophonium, neostigmine, physostigmine, pyridostigmine, echothiophate
Bethanechol
direct cholinergic agonist
activates bowel and bladder smooth muscle
used for post-op ileum, neurogenic ileum, urinary retention
resistant to AChE
Carbachol
direct cholinergic agonist mimics ACh (but is resistant to AChE) constricts pupil and relieves intraocular pressure in open-angle glaucoma
Methacholine
direct cholinergic agonist
stimulates muscarinic receptors in airway when inhaled
Challenge test for diagnosis of asthma (causes bronchospasm)
Pilocarpine
direct cholinergic agonist
contracts ciliary muscle of eye (open-angle glaucoma), pupillary sphincter (close-angle glaucoma), resistant to AChE, can cross BBB
Potent stimulator of sweat, tears, and saliva
Open-angle and closed-angle glaucoma, xerostomia (Sjogren syndrome)
Galantamine, donepezil, rivastigmine
indirect cholinergic agonist (antiAChE)
increase ACh
used in Alzheimer disease (GDR -> Grandma Doesn’t Remember)
Edrophonium
indirect cholinergic agonist (antiAChE)
increases ACh
historically used to dx myasthenia gravis
Neostigmine
indirect cholinergic agonist (antiAChE)
increases ACh
No CNS penetration
used for post-op and neurogenic ileus, urinary retention, myasthenia gravis, reversal of NMJ blockade (post-op)
Physostigmine
indirect cholinergic agonist (antiAChE)
increases ACh
Antidote for anticholinergic toxicity
Crosses BBB
Pyridostigmine
indirect cholinergic agonist (antiAChE)
increases Ach, increases muscle strength
Used for Tx of myasthenia gravis (long acting)
does not cross BBB
Echothiophate
indirect cholinergic agonist (antiAChE)
glaucoma
What are potential complications of all ACh agonists to look out for?
exacerbation of COPD, asthma, and peptic ulcers when given to susceptible patients
Muscarinic antagonists
atropine, homatropine, tropicamide, cyclopentolate, benztropine, glycopyrrolate, hyoscyamine, dicyclomine, ipratropium, tiotropium, oxybutynin, scopolamine
Atropine, homatropine, tropicamide, cyclopentolate
muscarinic antagonists
target: eye
applications: produce mydriasis and cycloplegia (paralysis of the ciliary muscles)
homatropine, tropicamide, and cyclopentolate have a shorter duration of action than atropine, so used more often to dilate eyes
benztropine
muscarinic antagonist
target: CNS
uses: decreases side effects of antipsychotics, Parkinson disease, acute dystonia
glycopyrrolate
muscarinic antagonist
target: GI, respiratory
uses: parenteral: pre-op use to decrease airway secretions
oral: drooling, peptic ulcer
hyoscyamine, dicyclomine
muscarinic antagonist
target: GI
uses: antispasmodics for IBS
Ipratropium, tiotropium
muscarinic antagonist (inhaled)
target: respiratory
uses: decreases bronchoconstriction, COPD, asthma
oxybutinin
muscarinic antagonist
target: GU
uses: reduce bladder spasms and urge urinary incontinence (overactive bladder)
scopolamine
muscarinic antagonist (patch)
target: CNS
uses: motion sickness, decreases oral secretions in mechanically ventilated patients
What are adverse effects of atropine use?
can cause acute angle-closure glaucoma in elderly (due to mydriasis), urinary retention in men with BPH, and hyperthermia in infants
direct sympathomimetics
albuterol, almeterol, dobutamine, dopamine, epinephrine, isoproterenol, norepinephrine, phenylephrine, terbutaline, clonidine
indirect sympathomimetics
amphetamine, cocaine, ephedrine
albuterol, salmeterol
direct sympathomimetic
B2>B1 (inhaled)
use: albuterol for acute asthma or COPD
Salmeterol for long-term asthma or COPD control
adverse effect of albuterol
tachycardia
dobutamine
direct sympathomimetic
B1>B2, alpha
uses: HF, cardiac stress testing
effect: increases HR and contractility
dopamine
direct sympathomimetics Low doses = D1/D2 Medium doses = B1/B2 High doses = alpha1/alpha2 Uses: unstable bradycardia, HF, shock
epinephrine
direct sympathomimetics
B>alpha (alpha1, alpha2, B1, B2)
uses: anaphylaxis, asthma, croup, hypotension
isoproterenol
direct sympathomimetic
B1=B2
use: electrophysiologic evaluation of tachyarrhythmias
can worsen ischemia
norepinephrine
direct sympathomimetic
alpha1>alpha2>beta1
use: hypotension, septics shock, cariogenic shock
phenylephrine
direct sympathomimetic
alpha1>alpha2
uses: hypotension, ocular procedures (mydriasis), rhinitis (decongestant)
terbutaline
direct sympathomimetic
B2>B1
uses: bronchospasm, tocolysis
clonidine
direct sympathomimetic
alpha2
uses: decrease BP (can see significant rebound HTN)
ampethamine
indirect sympathomimetic
MOA: indirect agonist, reuptake inhibitor, releases stored catecholamines
uses: narcolepsy, obesity, ADHD
cocaine
indirect agonist, reuptake inhibitor
uses: causes vasoconstriction and local anesthesia
never give beta blockers if cocaine intoxication is suspected
ephedrine
indirect agonist, releases stored catecholamines
uses: nasal decongestion, urinary incontinence, hypotension
alpha2-agonists
clonidine, alpha-methyldopa
alpha-methyldopa
alpha2-agonist; Tx HTN in pregnancy
Nonselective alpha blockers
phenoxybenzamine, phentolamine
alpha 1 selection alpha blockers
prazosin, terazosin, doxazosin, tamsulosin
phenoxybenzamine
nonselective alpha blocker
uses: irreversible; pheochromocytoma to prevent catecholamine (HTN) crisis
AE: orthostatic hypotension, reflex tachycardia
Phentolamine
nonselective alpha blocker
uses: reversible; given to patients on MAO inhibitors who eat tyramine-containing food
AE: orthostatic hypotension, reflex tachycardia
Prazosin, terazosin, doxazosin, tamsulosin
alpha 1 selective blocker
uses: urinary symptoms of BPH, PTSD (prazosin), HTN (except tamsulosin - prostate specific)
AE: orthostatic hypotension, dizziness, headache, reflex tachycardia, rebound HTN with abrupt withdrawl
Nonselective beta blockers
nadolol, propranolol, timolol
B1 selectieve beta blockers
atenolol, esmolol, metoprolol, nebivolol
Weak B1/B2 agonists
acebutolol, pindolol
Nonselective alpha/beta blockers
carvedilol, labetalol
uses of beta blockers
HTN, CAD, CHF (slows), hyperthyroidism, migraine prophylaxis, anxiety, SVT, glaucoma, aortic dissection
what are the adverse effects of beta blockers?
bronchoconstriction, hypoglycemia, increased BP in cocaine user, rebound tachycardia, rebound HTN, arrhythmia
Avoid beta blocker use in patients with lung problems