SNS

Gq

Increases vascular smooth muscle contraction, increases pupillary dilator muscle contraction (mydriasis), increases intestinal and bladder sphincter muscle contraction

Decreases renin release

SNS

Gi

Decrease SNS outflow, Decrease Insulin release, Decrease Lipolysis, Increase Plt aggregation

Drugs that Block A2: Clonidine, Methyldopa, Yohimbine, Mertazapine

SNS

Gs

Increase HR, Increase Contractility, Increase Renin, Increase Lipolysis

SNS

Gs

Vasodilation, Bronchodilation, Increase HR, Increase Contractility, Increase Lipolysis, Increase Insulin resistance, Increase Aqueous Humor Production

Decrease Uterine tone (tocolysis); Ciliary muscle relaxation

*NE has NO B2 EFFECTS

PNS

Gq

CNS, Enteric nervous system; Increased Gastric Motility?

PNS

Gi

Decreased HR and Contractility of Atria (SA nodal tissue)

PNS

Gq

Increased exocrine gland secretions (i.e. lacrimal, salivary, gastric acis), Increased gut peristalsis, Increased bladder contraction, bronchconstriction, Increased pupillary sphincter muscle contraction (miosis), ciliary muscle contraction (accomodation)

Dopamine

Gs

Relaxes renal vascular smooth muscle

Dopamine

Gi

Modulates transmitter release, especially in the brain

Histamine

Gq

Increased nasal and bronchial mucus production, Increased Vascular permeability, contraction of bronchioles, pruritis, and pain

Histamine

Gs

Increased Gastric Acid Secretion

Vasopressin

Gq

Increased Vascular smooth muscle contraction

Vasopressin

Gs

Increased H2O permeability and reabsorption in the collecting tubules of the kidney (V2 is found in the 2 Kidneys)

H1 a1, V1, M1, M3

HAVe 1 M&M

IP3 DAG pathway

MAD 2's

M2, a2, D2

Inhibits Adenylyl cyclase

B1, B2, D1, H2, V2

Stimulate Adenylyl cyclase

These drugs decrease release of NE

Clonidine

Methyldopa

Yohimbine

Mirtazapine

Cholinomimetic

Use: Postoperative ileus, neurogenic ileus and urinary retention

Action: Activates bowel and bladder smooth muscle; resistant to AChE. "Bethany, call (bethanechol) me, maybe, if you tant to activate your bowels and bladder."

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

Cholinomimetic agent

Clinical: Glaucoma, pupillary constriction, and relief of intraocular pressure

Action: Carbon copy of acetylcholine

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

Cholinomimetic agent

Clinical: Potent stimulator of sweat, tears and saliva; Open-angle and closed angle glaucoma

Action: Contracts ciliary muscle of eye (open-angle glaucoma), pupillary sphincter (closed-angle glaucoma); resistant to AChE. "You cry, drool, and sweat on your 'pillow'".

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

Cholinomimetic

Clinical: Challenge test for diagnosis of asthma

Action: Stimulates muscarine receptors in airway when inhaled. 

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

AChEsterase

Clinical: Postpop and neurogenic ileus and urinary retention, myasthenia gravis, reversal of NMJ block (post op)

Action: Increase endogenous ACh. 

Neo CNS = No CNS penetration

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

AChEsterase

Clinical: Myasthenia gravis (long acting); does not penetrate CNS

Action: Increase endogenous ACh; Increase strength. Pyridostigmine gets rid of myasthenia gravis

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

AChEsterase

Clinical: Anticholinergic toxicity (crosses blood-brain barrier -> CNS)

Action: Increase endogenous ACh. Physostigmine "phyxes" atropine overdose

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

AChE

Clinical: Alzheimer's disease

Action: Increases endogenous ACh

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

Other Drugs: Rivastigmine, Galantamine

AChE

Clinical: Alzheimer's disease

Action: Increases endogenous ACh

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

Other Drugs: Donepezil, Galantamine

AChE

Clinical: Alzheimer's disease

Action: Increases endogenous ACh

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

Other Drugs: Rivastigmine, Donepezil

AChEsterase

Clinical: Historically, diagnosis of myasthenia gravis (extremely short acting). Myasthenis now diagnosed by anti-AChR Ab (anti-acetylcholine receptor antibody) test.

Action: Increase endogenou ACh

Side Effects: Watch for exacerbation of COPD, asthma and peptic ulcers

DUMBBELSS (aka PNS stimulation)

Diarrhea, Urination, Miosis, Bronchospasm, Bradycardia, Excitation of skeletal muscle and CNS, Lacrimation, Sweating and Salivation

Often due to organophosphates, such as parathion, that irreversibly inhibits AChE; found in insecticides; poisoning usually seen in farmers

Antidote - atropine (competitive inhibitor) + pralidoxime (regenerates AChE if given early)

Muscarinic antagonist

Organ: Eye

Application: Produce mydriasis and cycloplegia

Other Drugs: homatropine, tropicamide

Muscarinic antagonist

Organ: Eye

Application: Produce mydriasis and cycloplegia

Other Drugs: Atropine, Tropicamide

Muscarinic antagonist

Organ: Eye

Application: Produce mydriasis and cycloplegia

Other Drugs: Atropine, homatropine

Muscarinic Antagonist

Organ: CNS

Applications: Parkinson's disease - "Park my Benz"

Muscarinic Antagonist

Organ: CNS

Applications: Motion Sickness

Muscarinic antagonist

Organ: Respiratory system

Application: COPD, asthma ("I pray I can breath soon!")

Other Drugs: Tiotropium

Muscarinic antagonist

Organ: Respiratory system

Application: COPD, asthma ("I pray I can breath soon!")

Muscarinic antagonist

Organ: Genitourinary

Applications: Reduce urgency in mild cystitis and reduce bladder spasms

Muscarinic antagonist

Organ: Gastrointestinal, respiratory

Applications:

-Parenteral: preoperative use to reduce airway secretions

-Oral: drooling, peptic ulcer

Muscarinic Antagonist

Use: Bradycardia, ophthalmic applications

Organs: Eye=↑pupil ↑pupil dilation; Airway =↓secretions Stomach = ↓acid secretion; Gut = ↓motility; Bladder = ↓urgency in cystitis

Action: blocks DUMBBeLSS

Diarrhea, Urination, Miosis, Bronchospasm, Bradycardia, Lacrimation, Sweating and Salivation; skeletal muscle and CNS excitation mediated by nicotinic receptors

Toxicity: Hot as a hare, Dry as a bone, Red as a beet, Blind as a bat, Mad as a hatter; can be cause by Jimson weed (Datura) -> gardener's pupil (mydriasis due to plant alkaloids)

Can cause acute angle-closure glaucoma in elderly (due to mydriasis), urinary retention in men with prostatic hyperplasia and hyperthermia in infants

Sympathomimetic

Effec: B (at low dose) >a (at high dose)

Applications: Anaphylaxis, open angle glaucoma, asthma, hypotension; alpha effects predominate at high doses

Sympathomimetic

a1>a2>B1

Applications: Hypotension (but ↓ renal perfusion)

Sympathomimetic

B1=B2

Applications: Electrophysiologic evaluation of tacharrhythmias. Can worsen ischemia

Sympathomimetic

D1=D2>B>a

Applications: Unstable bradycardia, heart failure, shock; inotropic and chronotropic a effects predominat at high doses

Sympathomimetic

B1>B2, a

Applications: Heart failure (inotropic>chronotropic), cardiac stress testing

Sympathomimetic

a1>a2

Hypotension (vasoconstrictor), ocular procedure (mydriatic), rhinitis (decongestant)

Sympathomimetic

B2>B1

Applications: Acute asthma

Similar Drugs: Salmetrol, Terbutaline

Sympathomimetic

B2>B1

Applications: Long term asthma or COPD

Similar drugs: Albuterol, terbutaline

Sympathomimetic

B2>B1

Applications: Reduce premature uterine contractions

Similar drugs: Albuterol, Salmetrol

Indirect sympathomimetic

Effect: Indirect general agonist, reuptake inhibitor, also releases stored catecholamines

Applications: Narcolepsy, obesity, ADD

Indirect Sympathomimetic

Effect: Indirec general agonist, releases stored catecholamines

Applications: Nasal decongestion, urinary incontinence, hypotension

Indirect sympathomimetic

Effect: Indirect general agonist, reuptake inhbitor

Applications: Causes vasoconstriction and local anesthesia; never give B-blockers if cocaine intoxication is suspected (can lead to unopposed a1 activation and extreme hypertension)

Sympatholytic (a2-agonist)

Applications: Hypertensive urgency (limited situations); does not decrease renal blood flow; ADHD, severe pain and a variety of off-label indications (e.g. ethanol and opioid withdrawal)

Toxicity: CNS depression, bradycardia, hypotension, respiratory depression, and small pupil size

Sympatholytic (a2-agonist)

Applications: Hypertension in pregnancy, safe in pregnancy

Toxicity: Direct Coombs +, hemolytic anemia, SLE-like syndrome

Nonselective alpha blocker - irreversible

Application: Pheochromocytoma (use phenoxybenzamine before removing tumor, since high levels of released catecholamines will not be able to overcome blockage)

Toxicity: Orthostatic hypotension, reflex tachycardia

Nonselective alpha blocker - reversible

Applications: Give to pts on MAOI who eat tyramine-containing foods

a1 blocker (-zosin)

Application: HTN, urinary retention in BPH

Tox: 1st-dose orthostatic hypotension, dizziness, headache

a1 blocker (-zosin)

Application: HTN, urinary retention in BPH

Tox: 1st-dose orthostatic hypotension, dizziness, headache

a1 blocker (-zosin)

Application: HTN, urinary retention in BPH

Tox: 1st-dose orthostatic hypotension, dizziness, headache

a2 blocker

Application: Depression

Tox: Sedation, ↑ serum cholestrol, ↑ appetite

A BEAM = B1 antagonists (B1>B2) - Acebutolol (partial agonist), Betaxolol, Esmolol (Short acting), Atenolol, Metoprolol

Use: HTN, angina pectoris, MI, SVT (propranolol, esmolol), CHF, Glaucoma

Toxicity: impotence, exacerbation of asthma, CV effects, CNS effects (sedation, sleep alteration); use with caution in diabetics

Please Try Not βeing Picky = Propranolol, Timolol, Nadolol and Pindolol

Use: HTN, angina pectoris, MI, SVT (propranolol, esmolol), CHF, Glaucoma

Toxicity: impotence, exacerbation of asthma, CV effects, CNS effects (sedation, sleep alteration); use with caution in diabetics

Carvedilol

Labetalol

a-agonist

↑ outflow of aqeuous humor

Side effects: Mydriasis, stinging; do not use in closed-angle glaucoma

↓aqueous humor synthesis

Side effects: No pupillary or vision changes

Timolol, betaxolol, carteolol

↓aqueous humor secretion

Side effects: No pupillary or vision changes

Pilocarpine, carbachol, physostigmine, echothiophate

Mechanism: Ciliary muscle contraction, opening of trabecular meshwork; ↑ outflow of aqueous humor

Side effects: Miosis, cyclospasm

Acetazolamide, dorzolamide, brinzolamide

Mechanism: decrease aqueous humor secretion due to decreased HCO3- (via inhibition of carbonic anhydrase)

Side effects: No pupillary or vision changes

Prostaglandin for Glaucoma

Mechanism: Increased outflow of aqueous humor

Side effects: Darkens color of iris (browning)

Not used clinically

Competes with choline for uptake into presynaptic cleft

Inhibits synaptobrevin (snare protein) inhibitng fusion of vessicles to the presynaptic membrane

result is flaccid paralysis; prevents sweating too

Inhibits conversion of Tyrosine to DOPA

Decrease sympathetic outflow

Inhibits packaging of catecholamines into presynaptic vessicles

Decrease sympathetic outflow

Replaces the Catecholamines in the presynaptic vessicles

Decrease sympathetic outflow