Autonomic Drugs

Question 1

Autonomic Drugs

Albuterol, salmeterol

Answer 1

Direct sympathomimetic
Action: β2 > β1
Applications: Albuterol for acute asthma or COPD. Salmeterol for long-term asthma or COPD control

Question 2

Autonomic Drugs

Dobutamine

Answer 2

Direct sympathomimetic
Action: β1 > β2, α
Applications: Heart failure (inotropic > chronotropic), cardiac stress testing

Question 3

Autonomic Drugs

Dopamine

Answer 3

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

Question 4

Autonomic Drugs

Epinephrine

Answer 4

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

Question 5

Autonomic Drugs

Fenoldopam

Answer 5

Direct sympathomimetic
Action: D1
Applications: Postoperative hypertension, hypertensive crisis. Vasodilator (coronary, peripheral, renal, and splanchnic). Promotes natriuresis. Can cause hypotension and tachycardia.

Question 6

Autonomic Drugs

Isoproterenol

Answer 6

Direct sympathomimetic
Action: β1 = β2
Applications: Electrophysiologic evaluation of tachyarrhythmias. Can worsen ischemia

Question 7

Autonomic Drugs

Midodrine

Answer 7

Direct sympathomimetic
Action: α1
Applications: Autonomic insufficiency and postural hypotension. May exacerbate supine hypertension.

Question 8

Autonomic Drugs

Norepinephrine

Answer 8

Direct sympathomimetic
Action: α1 > α2 > β1
Applications: Hypotension, septic shock.

Question 9

Autonomic Drugs

Phenylephrine

Answer 9

Direct sympathomimetic
Action: α1 > α2
Applications: Hypotension (vasoconstrictor), ocular procedures (mydriatic), rhinitis (decongestant)

Question 10

Autonomic Drugs

Amphetamine

Answer 10

Indirect sympathomimetic
Action: Indirect general agonist, reuptake inhibitor, also releases stored catecholamines
Applications: Narcolepsy, ADHD, obesity.

Question 11

Autonomic Drugs

Cocaine

Answer 11

Indirect sympathomimetic
Action: Indirect general agonist, reuptake inhibitor
Applications: Causes vasoconstriction and local anesthesia. Never give β blockers if cocaine intoxication is suspected.

Question 12

Autonomic Drugs

Ephedrine

Answer 12

Indirect sympathomimetic
Action: Indirect general agonist, releases stored catecholamines
Applications: Nasal decongestion, urinary incontinence, hypotension

Question 13

Autonomic Drugs

Atropine, homatropine, tropicamide

Answer 13

Muscarinic antagonist
Organ System: Eye
Application: Produce mydriasis and cycloplegia

Question 14

Autonomic Drugs

Benztropine

Answer 14

Muscarinic antagonist
Organ System: CNS
Application: Parkinson disease, acute dystonia.

Question 15

Autonomic Drugs

Glycopyrrolate

Answer 15

Muscarinic antagonist
Organ System: GI, respiratory
Application: 
Parenteral: perioperative use to reduce airway secretions
Oral: Drooling, peptic ulcer

Question 16

Autonomic Drugs

Hyoscyamine

Answer 16

Muscarinic antagonist
Organ System: GI
Application: Antispasmodics for irritable bowel syndrome

Question 17

Autonomic Drugs

Ipratropium, tiotropium

Answer 17

Muscarinic antagonist
Organ System: Respiratory
Application: COPD, asthma

Question 18

Autonomic Drugs

Oxybutynin, solifenacin, tolterodine

Answer 18

Muscarinic antagonist
Organ System: Genitourinary
Application: Reduce bladder spasms and urge urinary incontinence (overactive bladder)

Question 19

Autonomic Drugs

Scopolamine

Answer 19

Muscarinic antagonist
Organ System: CNS
Application: Motion sickness

Question 20

Autonomic Drugs

Atropine

Answer 20

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.

Question 21

Autonomic Drugs

Bethanechol

Answer 21

Direct cholinergic agonist
Action: Activates bowel and bladder smooth muscle; resistant to AChE.
Applications: Postoperative ileus, neurogenic ileus, urinary retention

Question 22

Autonomic Drugs

Carbachol

Answer 22

Action: Direct cholinergic agonist
Applications: Constricts pupil and relieves intraocular pressure in open-angle glaucoma

Question 23

Autonomic Drugs

Methacholine

Answer 23

Direct cholinergic agonist
Action: Stimulates muscarinic receptors in airway when inhaled
Applications: Challenge test for diagnosis of asthma

Question 24

Autonomic Drugs

Pilocarpine

Answer 24

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)

Question 25

Autonomic Drugs

Donepezil, galantamine, rivastigmine

Answer 25

Indirect cholinergic agonist (acetylcholinesterase)
Action: ↑ ACh
Applications: Alzehimer disease

Question 26

Autonomic Drugs

Edrophonium

Answer 26

Indirect cholinergic agonist (acetylcholinesterase)
Action: ↑ ACh
Applications: Historically, diagnosis of myasthenia gravis (extremely short acting).

Question 27

Autonomic Drugs

Neostigmine

Answer 27

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)

Question 28

Autonomic Drugs

Physostigmine

Answer 28

Indirect cholinergic agonist (acetylcholinesterase)
Actions: ↑ ACh.
Applications: Anticholinergic toxicity: crosses BBB (tertiary amine)

Question 29

Autonomic Drugs

Pyridostigmine

Answer 29

Indirect cholinergic agonist
Action: ↑ ACh; ↑ muscle strength
Applications: Myasthenia gravis (long acting); does not penetrate CNS (quarternary amine)

Question 30

Autonomic Drugs

Clonidine, guanfacine

Answer 30

Action: α2 agonist
Applications: Hypertensive urgency (limited siutations), ADHD, Tourette syndrome
Adverse Effects: CNS depression, bradycardia, hypotension, respiratory distress, miosis

Question 31

Autonomic Drugs

α-methyldopa

Answer 31

Action: α2 agonist
Applications: Hypertension in pregnancy
Adverse Effects: Direct Coombs ⊕ hemolysis, SLE-like syndrome

Question 32

Autonomic Drugs

Phenoxybenzamine

Answer 32

Irreversible nonselective α blocker
Applications: Pheochromocytoma (used preoperatively) to prevent catecholamine (hypertensive) crisis
Adverse Effects: Orthostatic hypotension, reflex tachycardia

Question 33

Autonomic Drugs

Phentolamine

Answer 33

Reversible nonselective α blocker
Applications: Give to patients on MAO inhibitors who eat tyramine-containing foods
Adverse Effects: Orthostatic hypotension, reflex tachycardia

Question 34

Autonomic Drugs

Prazosin, terazosin, doxazosin, tamsulosin

Answer 34

α1 selective blockers
Applications: Urinary symptoms of BPH; PTSD (prazosin); hypertension (except tamsulosin)
Adverse Effects: 1st dose orthostatic hypotension, dizziness, headache

Question 35

Autonomic Drugs

Mirtazapine

Answer 35

α2 selective blockers
Applications: Depression
Adverse Effects: Sedation, ↑ serum cholesterol, ↑ appetite