Muscarinic Agonists

Drug Name Mechanism of Action Effects of Drug Adverse Effects Clinical Usefulness Nursing Considerations

BethanecholStimulates the

parasympathetic response, binds

irreversibly to the muscarinic receptors.

“Guy by the pool reading a dirty

magazine” Increased sweating,

salivation, GI motility, and urination. Decreased HR,

BP(vasodilation). Miosis(pupil constriction.

Bronchial constriction.

Hypotension, bradycardia, diarrhea,

exacerbation of asthma.

Pilocarpine-can reach toxic levels with

certain mushrooms, administer atropine

in this case.

Treats urinary retention

Monitor BP, advise pt to get up slowly,

monitor diarrhea, do not give to asthma

pt/COPD.Pilocarpine Treats glaucoma and

dry mouth

Muscarinic Antagonists

Drug Name Mechanism of Action Effects of Drug Adverse Effects Clinical Usefulness Nursing Considerations

AtropineBinds reversibly to

block the parasympathetic response & the

effects of Ach on the muscarinic receptors.

“Opposite of guy by the pool reading a dirty magazine or

Tiger in a dark room”DRY! Decreased

sweating, salivation, GI motility &

urination. Increased HP, BP. Mydriasis (dialated eyes).

Bronchial dialation.

HTN, Tachycardia, dry mouth, constipation,

urinary retention, viscous respiratory secretions. Toxicity with Oxybutynin or

Ipratropium and Belladonna flowers.

Pupillary dialation durin exam, treats

symptomatic bradycardia &

diarrhea

Monitor for HTN, constipation, urinary

retention, have pt drink fluids to

prevent viscous secretions.

Oxybutynin Treats overactive bladder

Ipratropium bromideTreats asthma and

COPD

Cholinesterase Inhibitors

Drug Name Mechanism of Action Effects of Drug Adverse Effects Clinical Usefulness Nursing Considerations

NeostigmineACh doesn’t

breakdown especially at Nicotinic M

receptors in skeletal muscle -> increase in

Ach available.

Increased force of skeletal muscle

contraction, mild CNS stimulation.

Bradycardia, excessive salivation,

urinary urgency. “GBTP”

Toxicity- can cause neuromuscular

blockade/ extreme parasympathetic

stim, brochoconstriction and paralysis. Treat

toxicity with mechanical

ventilation and muscarinic antagonist

(Atropine)

Two types:

Reversible-myasthenia gravis

(lack of Ach receptors) and some

Alzheimer’s pts.

Irreversible- chemical warfare/insecticides.

Monitor vital signs (especially HR),

incontinence and paralysis.

Neuromuscular Blocking Agents

Types Drug Name Mechanism of Action

Effects of Drug Adverse Effects Clinical Usefulness

Nursing Considerations

Competitive

-ium Suffix

CistracuriumPancuroniumRocuroniumVecuronium

Blocks Ach from binding, causes

muscle relaxation w/ no

depolarization when they bind. Work as long as conc of drug is

higher than conc of Ach.

Muscle relaxation Hypotension w/ Atracurium,

respiratory arrest (paralyze the diaphragm).

Toxicity- admin cholinesterase inhibitor to inc

amt of Ach.

Relaxes muscles during SX, tracheal

intubation, mechanical

ventilation & ARDS

Monitor RR, BP. Watch for signs of respiratory arrest, turn and position pts, mouth care, IV admin only.

DO NOT ALTER PAIN OR

CONSCIOUSNESS -> must also give

pt a sedative.

Do not cross BBB or placenta -> must be given

through IV.

Depolarizing Succinylcholine

Causes initial depolarization when bound to

Nicotinic M receptors but

does not allow repolarization.

Initial contraction followed by

paralysis.

Malignant hyperthermia (inc

temp), post-op muscle pain,

hyperkalemia.

Adrenergic Receptors

Alpha 1- “Alpha Male” eyes, blood vessels, GU

Mydriasis (pupil dialation) Vasoconstriction of the skin, visceral organs & mucous

membranes Ejaculation Tight urinary sphincter & prostate INCREASED BP

Alpha 2- CNS only Inhibits the release of NE Assists w/ HR & BP control Involved w/ pain relief

Beta 1- “one heart & one kidney”

INCREASED HR & CONTRACTION INTENSITY INCREASED CONDUCTION SPEED RAAS increased volume (Na/H2O rentention) and

vasoconstriction -> INCREASED BP

Beta 2- “2 lungs, 2nd person, 2 types of diabetes”

Bronchial dialation Relaxation of uterine smooth muscle Vasodialation of heart, lungs and skeletal muscle (shunting of

blood to main organs) Gluconeogenesis(by the liver for energy)

Dopaminergic Peripherally dialates the renal blood vessels

Adrenergic Agonists- SNS always monitor VS

Drug Name Mechanism of Action Effects of Drug Adverse Effects Clinical Usefulness Nursing Considerations

Epinephrine Adrenaline, Sympathetic

stimulation, Works on a1, a2, b1, b2 receptors SNS

response.Epinephrine is a catecholamine

Ephedrine is not

Increased BP, vasoconstriction, urinary retention

and bronchodialation,

nasal decongestant

HTN, reflex bradycardia, necrosis

Treats cardiac arrest and anaphylactic

shockIV SubQ or IM admin

Ephedrine Treats nasal congestion. PO or IV admin

NorepinephrineCatecholamine a1, a2, b1

w/o b2 SNS responseSNS a1, a2, b1

NOT b2 HTN Treats hypotension IV admin

DobutamineBeta 1 only, catecholamine

Beta 1 onlyHTN Treats heart failure IV admin

PhenylephrineAlpha 1 only,

noncatecholamineAlpha 1 only HTN/ extreme SNS

response

Treats nasal congestion locally and hypotension

when given through IV

PO or IV admin

Albuterol Beta 2 only, noncatecholamine

Beta 2 only HypotensionBronchodialation for pts w/ asthma, better

than isoproterenol due to specificity.

PO admin

Dopamine

Dopamine receptors- low dose

Dop & Beta 1- mid range dose

Dop, Beta 1 & Alpha 1- high dose

LD- dilates kidney vessels

MD- also inc HRHD- also Alpha 1

response

HTN, tachycardia, opposite of “guy by

the pool”

Treats shock, heart failure and acute

renal failure.IV admin

Adrenergic Antagonists

Reversible blocking of adrenergic receptors, get opposite effect of a1, a2, b1, b2 depending on the receptor being blocked.

Types Drug Name Mechanism of Action

Effects of Drug Adverse Effects Clinical Usefulness Nursing Considerations

Alpha Antagonists

-osin

PrazosinBlock Alpha 1 Opposite of

Alpha Male

Orthostatic hypotension, reflex

tachycardia and nasal congestion.

Treats HTN, BPH, pheocromocytoma.

Reversal of an alpha 1 agonist OD.

Monitor BP & HR. Check pt for

heart disease prior. Tell pt to

get up slow- Orthostatic

hypotension.

Doxazosin

Tamsulosin

Beta Antagonists

-olol

Propanolol

Block Beta 1 (heart

specifically)

Nonspecific Beta blocker. Reduces HR.

Bradycardia, decreased CO, AV

heart block. Bronchoconstriction and hypoglycemia.

Treats HTN, angina and arrhythmias.

MI, hyperthyroidism and stage fright.

Dangerous for asthmatic, COPD and

diabetic pts due Beta 2 blocking. Check vitals HR,

BP RR! Orthostatic

hypotension teaching.

Metroprolol Beta 1 specific

Bradycardia, decreased CO, AV

heart block.

Check vitals HR. Orthostatic

hypotension teaching. Good Beta blocker for

asthmatics.