Autonomic Drugs Flashcards
Autonomic Drugs
Albuterol, salmeterol
Direct sympathomimetic
Action: β2 > β1
Applications: Albuterol for acute asthma or COPD. Salmeterol for long-term asthma or COPD control
Autonomic Drugs
Dobutamine
Direct sympathomimetic
Action: β1 > β2, α
Applications: Heart failure (inotropic > chronotropic), cardiac stress testing
Autonomic Drugs
Dopamine
Direct sympathomimetic
Action: D1=D2 > β > α
Applications: Unstable bradycardia, HF, shock; inotropic and chronic effects at lower doses due to β effects; vasoconstriction at high doses due to α effects
Autonomic Drugs
Epinephrine
Direct sympathomimetic
Action: β > α
Applications: Anaphylaxis, asthma, open-angle glaucoma; α effects predominate at high doses. Significantly stronger effect at β2 receptor than norepinephrine
Autonomic Drugs
Fenoldopam
Direct sympathomimetic
Action: D1
Applications: Postoperative hypertension, hypertensive crisis. Vasodilator (coronary, peripheral, renal, and splanchnic). Promotes natriuresis. Can cause hypotension and tachycardia.
Autonomic Drugs
Isoproterenol
Direct sympathomimetic
Action: β1 = β2
Applications: Electrophysiologic evaluation of tachyarrhythmias. Can worsen ischemia
Autonomic Drugs
Midodrine
Direct sympathomimetic
Action: α1
Applications: Autonomic insufficiency and postural hypotension. May exacerbate supine hypertension.
Autonomic Drugs
Norepinephrine
Direct sympathomimetic
Action: α1 > α2 > β1
Applications: Hypotension, septic shock.
Autonomic Drugs
Phenylephrine
Direct sympathomimetic
Action: α1 > α2
Applications: Hypotension (vasoconstrictor), ocular procedures (mydriatic), rhinitis (decongestant)
Autonomic Drugs
Amphetamine
Indirect sympathomimetic
Action: Indirect general agonist, reuptake inhibitor, also releases stored catecholamines
Applications: Narcolepsy, ADHD, obesity.
Autonomic Drugs
Cocaine
Indirect sympathomimetic
Action: Indirect general agonist, reuptake inhibitor
Applications: Causes vasoconstriction and local anesthesia. Never give β blockers if cocaine intoxication is suspected.
Autonomic Drugs
Ephedrine
Indirect sympathomimetic
Action: Indirect general agonist, releases stored catecholamines
Applications: Nasal decongestion, urinary incontinence, hypotension
Autonomic Drugs
Atropine, homatropine, tropicamide
Muscarinic antagonist
Organ System: Eye
Application: Produce mydriasis and cycloplegia
Autonomic Drugs
Benztropine
Muscarinic antagonist
Organ System: CNS
Application: Parkinson disease, acute dystonia.
Autonomic Drugs
Glycopyrrolate
Muscarinic antagonist Organ System: GI, respiratory Application: Parenteral: perioperative use to reduce airway secretions Oral: Drooling, peptic ulcer
Autonomic Drugs
Hyoscyamine
Muscarinic antagonist
Organ System: GI
Application: Antispasmodics for irritable bowel syndrome
Autonomic Drugs
Ipratropium, tiotropium
Muscarinic antagonist
Organ System: Respiratory
Application: COPD, asthma
Autonomic Drugs
Oxybutynin, solifenacin, tolterodine
Muscarinic antagonist
Organ System: Genitourinary
Application: Reduce bladder spasms and urge urinary incontinence (overactive bladder)
Autonomic Drugs
Scopolamine
Muscarinic antagonist
Organ System: CNS
Application: Motion sickness
Autonomic Drugs
Atropine
Used to treat bradycardia and for ophthlamic applications Actions: Eye: ↑ pupil dilation, cycloplegia Airway: ↓ secretions Stomach: ↓ acid secretion Gut: ↓ motility Bladder: ↓ urgency in cystitis Adverse Effects: ↑ body temperature ( due to ↓ sweating), rapid pulse, dry mouth, dry, flushed skin, cycloplegia, constipation, disorientation. Can cause acute close-angle glaucoma in elderly, urinary retention in men with BPH, and hyperthermia in infants.
Autonomic Drugs
Bethanechol
Direct cholinergic agonist
Action: Activates bowel and bladder smooth muscle; resistant to AChE.
Applications: Postoperative ileus, neurogenic ileus, urinary retention
Autonomic Drugs
Carbachol
Action: Direct cholinergic agonist
Applications: Constricts pupil and relieves intraocular pressure in open-angle glaucoma
Autonomic Drugs
Methacholine
Direct cholinergic agonist
Action: Stimulates muscarinic receptors in airway when inhaled
Applications: Challenge test for diagnosis of asthma
Autonomic Drugs
Pilocarpine
Direct cholinergic agonist
Actions: Contracts ciliary muscle of eye (open-angle glaucoma), pupillary sphincter (closed-angle glaucoma); resistant to AChE.
Applications: Potent stimulator of sweat, tears, and saliva. Open-angle and closed angle glaucoma, xerostomia (Sjogren syndrome)
Autonomic Drugs
Donepezil, galantamine, rivastigmine
Indirect cholinergic agonist (acetylcholinesterase)
Action: ↑ ACh
Applications: Alzehimer disease
Autonomic Drugs
Edrophonium
Indirect cholinergic agonist (acetylcholinesterase)
Action: ↑ ACh
Applications: Historically, diagnosis of myasthenia gravis (extremely short acting).
Autonomic Drugs
Neostigmine
Indirect cholinergic agonist (acetylcholinesterase)
Action: ↑ ACh (No CNS penetration)
Applications: Postoperative and neurogenic ileus and urinary retention, myasthenia gravis, reversal of neuromuscular junction blockade (postoperative)
Autonomic Drugs
Physostigmine
Indirect cholinergic agonist (acetylcholinesterase)
Actions: ↑ ACh.
Applications: Anticholinergic toxicity: crosses BBB (tertiary amine)
Autonomic Drugs
Pyridostigmine
Indirect cholinergic agonist
Action: ↑ ACh; ↑ muscle strength
Applications: Myasthenia gravis (long acting); does not penetrate CNS (quarternary amine)
Autonomic Drugs
Clonidine, guanfacine
Action: α2 agonist
Applications: Hypertensive urgency (limited siutations), ADHD, Tourette syndrome
Adverse Effects: CNS depression, bradycardia, hypotension, respiratory distress, miosis
Autonomic Drugs
α-methyldopa
Action: α2 agonist
Applications: Hypertension in pregnancy
Adverse Effects: Direct Coombs ⊕ hemolysis, SLE-like syndrome
Autonomic Drugs
Phenoxybenzamine
Irreversible nonselective α blocker
Applications: Pheochromocytoma (used preoperatively) to prevent catecholamine (hypertensive) crisis
Adverse Effects: Orthostatic hypotension, reflex tachycardia
Autonomic Drugs
Phentolamine
Reversible nonselective α blocker
Applications: Give to patients on MAO inhibitors who eat tyramine-containing foods
Adverse Effects: Orthostatic hypotension, reflex tachycardia
Autonomic Drugs
Prazosin, terazosin, doxazosin, tamsulosin
α1 selective blockers
Applications: Urinary symptoms of BPH; PTSD (prazosin); hypertension (except tamsulosin)
Adverse Effects: 1st dose orthostatic hypotension, dizziness, headache
Autonomic Drugs
Mirtazapine
α2 selective blockers
Applications: Depression
Adverse Effects: Sedation, ↑ serum cholesterol, ↑ appetite
