Pharm II Flashcards
(49 cards)
Epinephrine
Β>α,
low dose ↑ systolic ↓diastolic ↑CO
High dose α ↑BP vasoconstriction, ↑HR
-Bronchospasm β2 dilate, α1 ↓secretions
Use: Anaphylaxis, Cardiac arrest, bronchospasm
Toxicity: Arrhythmia
Contraindication: Late term pregnancy
Norepinephrine
α1, α2, β1:
vasoconstriction, ↑TPR ↑HR
β1↑systolic, α↑diastolic
*Baroreceptor reflex ↓HR from ↑↑BP
Use: Vasodilatory shock
Toxicity:
Ischemia
Arrhythmia
hypertension
Contraindication: Pre-existing vasoconstriction/ischemia,
late term pregnancy
Dopamine
D>β>α
Low dose D ↓TPR (at splanchnic vessels*)
Medium β1 ↑HR
Higher α ↑BP ↑TPR, vasoconstriction
Use: Hypotension due to low CO secondary to cardiogenic shock
Toxicity:
Low dose-hypotension
High dose-ischemia
Contraindication:
Uncorrected tachyarrhythmia or Ventricular Fibrillation
indirect sympathomimetics
Amphetamine Methamphetamine Methylphenidate Ephedrine Pseudophedrine Thyramine
Amphetamine Methamphetamine Methylphenidate Ephedrine Pseudophedrine Thyramine **A man mainly eats pizza toppings*
reverse reuptake channel- ↑ Ca independent release
Cardio: α vasocronstriction, ↑ diastolic; β ↑HR, contraction, ↑systolic ((May get baro ↓HR) balanced)
CNS: stimulant, anorexia agent
Toxicity: tachycardia
Use: ADD, narcolepsy, nasal congestion
Contraindication:Rx with MAO inhibitor 2wk, HTN
phenylephrine
α1 agonist-turns on α1
↑TPR ↑MAP ↓HR (baro reflex) Pupillary dilation
↓Broncho/sinus secretions
NOT at catecholamine
Use: SV tachycardia, Mydriatic, Nasal decongestant
Toxicity: Hypertension
Contra: Hypertension, Ventricular tachycardia
Clonidine
α2 agonist (recall α2 paired to Gαi- inhibit)
acute: ↑BP=periph, chronic: ↓BP=central
cross BBB, reduces sympathetic stimulation from pre-motor neuron: ↓constriction ↓BP by ↓SNS
periphery= minor vasoconstriction
Use: Hypertension due to SNS drive
Toxicity:
Dry mouth (↓secrete)
Bradycardia
Sedation
WITHDRAWL can be life-threatening hypertensive crisis
Non-selective β blocker
Propranolol
Nadolol
timolol
Propranolol Nadolol timolol ↓HR ↓contractiity ↓renin release (BP) ↓SNS activation ↓aqueous humor (↓β)
Use: Hypertension, angina, glaucoma, early HF, arrhythmia
Contraindication: Bronchospasm=asthma Sinus bradycardia 2nd & 3rd Heart Block Cardiogenic shock
Cardioselective
Atenolol
Metoprolol
Esmolol= Emergent
Atenolol
Metoprolol
Esmolol= Emergent (IV, small t1/2)
↓HR ↓contractiity ↓renin release (BP)
↓SNS activation
Use: Hypertension, angina, arrythmia Hypotension
Toxicity: Bradycardia
Dizzy, depressed, insomnia
Contraindication: Sinus bradycardia
2nd & 3rd Heart Block
Cardiogenic shock
Partial Agonist both B1 and B2
Pindolol
↓BP ↓contractiity ↓renin release (BP)
↓SNS activation
Use: Hypertension when other BB not tolerated
Toxicity: Bradycardia
Dizzy, depressed, insomnia
Contraindication: Sinus bradycardia
2nd & 3rd Heart Block
Cardiogenic shock
Phenoxybenzamine
Irreversible α antagonist-covalently binds
↓BP (block α allows β)
↑chronotrpy/ionotrpy
Use: Hypertension with pheochromocytoma (adrenal tumor),
Vasoconstrictor induced extravasation (iv)
Toxicity:
Prolonged hypotension
Reflex Tachycardia
Nasal congestion
Contraindication:
Coronary artery disease
Phentolamine
Irreversible α antagonist-covalently binds
↓BP (block α allows β)
↑chronotrpy/ionotrpy
Use: Hypertension with pheochromocytoma (adrenal tumor),
Vasoconstrictor induced extravasation (iv)
Toxicity:
Prolonged hypotension
Reflex Tachycardia
Nasal congestion
Contraindication:
Coronary artery disease
Selective α1 antagonist
Prazosin
Doxazosin
Terazosin
Please Don’t Touch
Inhinits vasoconstriction
Relax prostate sm
Use: Hypertension
Benign prostatic hyperplasia (BPH)
Toxicity:
Syncopy
Orthostatic Hypertension
Nicotine
Stimulate Nn in CNS,
Used in smoking cessation
Succinylcholine
Block Nm- nicotinic receptors @nm junction
Use: Blocks depolarization, blocks muscle contraction
Used as muscle relaxant for intubation/CST
Contraindication: FAMILIAL HYPERTHERMIA or skeletal muscle myopathy, recent crush injury
Quaternary Nitrogen Analog
Acetylcholine
Methacholine
Carbachol
Betanechol
Acetylcholine
Binds nicotinic and muscarinic, rapidly hydrolyzed by cholinesterase
No therapeutic use
Methacholine
Bind muscarinic on sm and heart
Hydrolyze more slowly, longer t1/2
Used to Dx bronchial hyperactivity (asthma) Bronchilar constriction
Contraindication: Pt on β-blocker, antidote is β- agonist (dilate bronchiole)
Carbachol
Muscarinic and nicotinic, resistant to acetylcholinesterase
Use: Opthalmo miotic (constrict) to ↓pressure in glaucoma or post Sx
Toxicity: Excessive muscarinic and nicotinic activation, only for topical use
Bethenchol
Muscarinic only, resistant to hydrolysis
GI tract and bladder ↑Nm input (M3)
Less M2 (heart activation)
Use: NON-Obstructive urinary retention (post partum/post-op)
Contraindication: Bradycardia Peptic ulcer, asthma, bradycardia
Naturally occurring tertiary ammines
Muscarine
No therapeutic use, resist hydrolysis
Pilocarpine
Pure muscarinic activity, CROSS BBB, on eye it contracts ciliary muscle & sphincter, flattening iris and allowing drainage of Aq. H.
Use:Dry mouth (radiation and Sjogrens Syn),
Treat glaucoma,
Contraindication: Careful with pt on β-blocker may slow HR (conduction)
Cholinesterases
Acetylcholinesterase- synaptic cleft
Butyrylcholinesterase- plasma
Neostigmine
Reversible cholinesterase inhibitor, skeletal muscle endplate
Tx myasthenia gravis, the loss of Nm receptor Reverse neuromuscular blockade
Toxicity: excess Ach action at peripheral Muscarinic and nicotinic receptors
Contraindication: Intestinal obstruction (M1)
Endophonium
Inhibits cholinesterase reversibly, stimulates nicotinic receptors
(act fast and short)
Improve myasthenia gravis (not enough receptors, need more Ach), OR, worsen cholinergic crisis (too much Ach)
Use: Dx btwn Myasthenia gravis & Cholinergic crisis Toxicity: Bradycardia
Contraindication: Blocked intestinal or urinary tract
Physostigmine
Cross BBB, slow hydrolysis by cholinesterase Use: Counteract delirium
Toxicity: Convulsions,
Contraindications: Asthma, cardiac insufficiency, GI blockage
