ANS Meds Flashcards
Nervous System divisions
(see chart)
What does the SNS do?
Fight or flight response
ex. dilate pupils/bronchioles, increase HR, constrict vessels
What does the PsNS do?
Rest and digest
SLUDGE
ex. constrict pupils/bronchioles, decrease HR, dilate vessels, increase peristalsis, constrict bladder & dilate sphincter
What does SLUDGE stand for?
Salivation, lacrimation, urination, digestion, GI distress, emesis
PsNS
Define adrenergic, cholinergic, mimetic, agonist, antagonist
- Adrenergic –> sympathetic response, releases adrenaline
- Cholinergic –> parasympathetic response
- Mimetic –> mimics systemic effects
- Agonist –> works with the system to effect a response
- Antagonist –> works against the system to effect a response
How do adrenergics and cholinergics affect the SNS & PNS?
(see picture)
Adrenergic Agonists
- stimulate SNS
- affects Alpha 1 & 2, and Beta 1 & 2 receptors
see individual cards for effects
Alpha 1 Adrenergic agonists
A1 receptors are peripheral
sympathomimetic- turns SNS “on”
- increase cardiac contractility (inotropic), vasoconstriction
- dilate pupils/bronchioles
- increase HR
- increase glucose
- decrease uterine contractions, urination, GI motility
“Fight” response
Good for BP control
Alpha 2 Adrenergic agonists
does opposite of expected
- inhibits norepinephrine release
- promotes vasodilation, decreased BP
- decreased GI motility/tone
Beta 1 Adrenergic agonists
- Beta 1 receptors primarily in heart
- increase cardiac contractility, HR (inotropic)
- increases renin secretion & BP
“one heart”
Beta 2 Adrenergic agonists
- Beta 2 receptors primarily in lungs
- decreases GI tone/motility
- bronchodilation
- increased blood flow in skeletal muscles
- relaxes smooth muscles of uterus
- activates liver glycogenolysis (increases BG)
“two lungs”
ie. Albuterol
Dopaminergic receptors
- located in renal, mesenteric, coronary, and cerebral arteries
- vasodilation
only react to dopamine?
Classifications of adrenergic agonists
- Direct-acting –> directly stimulates adrenergic receptors (ie. epi/norepi)
- Indirect-acting –> stimulates release of norepi from terminal nerve endings (ie. amphetamines)
- Mixed-acting –> stimulates adrenergic receptor sites and release of norepi from terminal nerve endings (ie. ephedrines)
directs are natural, indirects and mixed are synthetic
Catecholamines
- produce sympathetic response
- endogenous (adrenal glands) - epi, norepi, dopamine (brain)
- synthetic - isoproterenol, dobutamine
Noncatecholamines
- stimulates adrenergic receptors
- most have longer duration than endogenous/synthetic
- phenylephrine, metaproterenol, albuterol
Epinephrine
(Adrenaline)
- nonselective adrenergic agonist
- endogenous catecholamine
- inotropic, vasoconstriction, bronchodilation
- monitor for IV infiltration/extravasation (phentolamine mesylate)
Albuterol
- noncatecholamine adrenergic agonist
- bronchodilation
- use cautiously in heart pts
Central-acting alpha 2 agonists
- act on CNS to promote vasodilation
- decreases norepinephrine release & peripheral adrenergic receptor activation
- Clonidine (HTN), methyldopa (version of dopamine)
Adrenergic antagonists
blockers
- blocks alpha and beta receptor sites & effects of adrenergic NTs
- directly by occupying receptor sites, or indirectly by inhibiting release of epi/norepi
Alpha adrenergic antagonists
alpha blockers
- promote vasodilation
- selective - blocks A1
- non-selective - blocks A1 & A2
- -sin ending
remember A2 does opposite
caution in resp issues
Beta adrenergic antagonists
beta blockers
- promote vasodilation (decrease HR & pulse)
- selective - blocks B1, fewer side effects
- nonselective - blocks B1 & B2 receptors –> bronchoconstriction
- -lol ending
caution in resp issues
Adrenergic neuron antagonists
- block release of norepinephrine (& other catecholamines/serotonin)
- decrease BP
ie. reserpine
st. john’s wort decrease effects
What is the neurotransmitter of the PNS?
acetylcholine (ACh)
What are the cholinergic receptors?
muscarinic (smooth muscles & heart) and nicotinic (skeletal muscles)
Direct vs indirect cholinergic agonists
direct acts on receptors, indirect inhibits acetylcholinesterase
PNS (cholinergic) acronym
SLUDGE
salvation, lacrimation, urination, digestion, GI distress, emesis
opposite of SNS
also vasodilation, bronchoconstriction
Direct-acting cholinergic agonists
- primarily selective to muscarinic receptors
- heart, GI/GU, glands
ie. metopclopramide, pilocarpine, bethanechol chloride
Metoclopramide
(Reglan)
increases gastric emptying
Pilocarpine
(Diocarpine)
contricts pupils
Bethanechol chloride
(Urecholine)
increase urination
Indirect-acting cholinergic agonists
- ## inhibits & converts cholinesterase enzyme into choline & acetic acid –> more ACh available
Cholinergic antagonists
- make SNS “leader”
- be careful with glaucoma
Atropine
- increase HR, decrease GI
- contraindicated in glaucoma
What kind of meds are antiparkinsonism drugs?
anticholinergics (indirect?)
Scopolomine
- transdermal anticholinergic
- treats nausea
- lasts for 3 days
What kinds of meds are contraindicated in glaucoma?
adrenergic agonists & anticholinergics
