Exam 4 Module 8 Drug Purpose Flashcards
4 main sympathetic receptors
Alpha 1
Alpha 2
Beta 1
Beta 2
Alpha 1
- Generally about stimulation
- Stimulation = more exictation, mydriasis, arterial constriction
- Block = less excitation, miosis, arterial vasodilation
Where are alpha 1 receptors located?
Eye, salivary glands, GI/GU sphincters, arterioles
phenylephrine (Sudafed PE)
Alpha 1 agonist
decongestant drug
doxazosin (Cardura)
- Alpha 1 receptor blocker
- Blocks sympathetic stimulation, we get relaxation
- Used for BPH
Alpha 2
- Generally about relaxation
- Stimulation = more relaxation
- Block = less relaxation
Where are alpha 2 receptors located?
Smooth muscle NMJ synapse
clonidine (Catapres)
- alpha 2 agonist
- Agonizes receptors and causes more relaxation
- Good BP medication
Beta 1
- Generally about stimulation
- Stimulation = more stimulation, increase conductivity, increase renin
- Block = less stimulation, decrease conductivity, decrease renin
Where are beta 1 receptors located?
Heart, brain, kidney
atenolol (Tenormin)
- Blocks beta 1 receptors in the heart
- selective antagonist
- less stimulation, decreases conductivity
- lowers BP
dobutamine (dobutrex)
- Beta 1 selective agonist
- Use in shock to improve the conductivity stimulation of the heart
Beta 2
- Generally about stimulation
- Stimulation = more stimulation, dilation, increase lipolysis, improves insulin
- Block = less stimulation, constriction, decrease lipolysis, impairs insulin
Where are beta 2 receptors located?
smooth muscle, bronchioles, liver, uterus
albuterol (Proventil)
- Beta 2 agonist
- Used to open airways
- dilation of the bronchioles by stimluating beta 2
- will also hit beta 1 which causes increased heart rate
terbutaline (Brethine)
- Beta 2 agonist
- Use for premature labor which causes the uterus to relax
If we over stimulate the sympathetic nervous system we will have….
-decrease in cardiac output because of too fast of heart rate, too slow of contraction
Adrenergic agonist/ sympathomimetic
- stimulate all of the adrenergic receptors in the SNS
- induce fight or flight
- frequently used to treat shock
Beta 1 selective adrenergic blocking agents
- Does not block the beta 1 receptors responsible for bronchodilation
- preferred in patients with respiratory problems
- used to treat HTN, angina, and HF
- must be tapered off
BP example with 4 receptors
Alpha 1 agonist = increase BP alpha 1 antagonist = decrease BP Alpha 2 agonist = decrease BP Alpha 2 antagonist = increase BP Beta 1/2 agonist = increase BP Beta 1/2 antagonist = decrease BP
Parasympathetic receptors
- Muscarinic: most are this
- Nicotinic: NMJ and ganglia
- “feed and breed”
Where are M1 receptors located?
CNS and enteric nervous system
Where are M2 receptors located?
heart
Where are M3 receptors located?
- exocrine glands
- GI
- eyes
- lungs
- GU
What is the primary neurotransmitter of the parasympathetic nervous system?
Ach
Stimulation of M3 in exocrine glands..
- increase exocrine gland secretion
- see patients sweating
Stimulation of M3 in the gut..
- increases gut motility
- go to the bathroom more often
Stimulation of M3 in pupillary sphincter…
-causes miosis: constriction of the pupil
Stimulation of M3 in ciliary muscle causes
accommodation: ability to focus near and far almost instantaneously
Stimulation of M3 in lungs and GU causes
broncho constriction and bladder constriction
bethanechol (Urecholine)
- direct acting cholinergic
- used for urinary retention
carbechol (Carbastat)
- direct acting cholinergic
- used for glaucoma, urinary retention
methacholine (Provocholine)
- direct acting cholinergic
- asthma challenge test
pilocarpine (Salagen)
- direct acting cholinergic
- used to test for cystic fibrosis
- sweat test
Anti-acetylcholine esterases cause you to become…
more cholinergic
Neostigmine (Prostigmin)
indirect cholinergic
- used in urinary retention
- used in myasthenia gravis
- used as an antidote to NMJ blockers
pyridostigmine (Mestinon)
indirect cholinergic
- used in urinary retention
- used in myasthenia gravis
- used as an antidote to NMJ blockers
physostigmine (Antilirium)
- indirect cholinergic
- FIXostigmine
- used to counteract atropine overdose
The rescue drug for an anticholinergic drug is…
cholinergic drug
donepezil (Aricept)
indirect cholinergic
- used to treat Alzheimer’s/dementia
- allows what Ach is there to be productive instead of being broken down
What receptors do anticholinergic drugs work on?
M1, M2, M3
Antagonizing M3 causes..
- Decrease exocrine secretions
- Decrease gut motility
- Mydriasis
- Cycloplegia (no accommodation)
- Broncho relaxation
- Bladder distention
atropine (Atreza)
- anticholinergic
- used to create mydriasis
- used as antidote to cholinergic poisoning
- used to prevent or slow down drooling
- used as a rescue drug for bradycardia
ipratropium (Atropent)
anticholinergic
- used to treat asthma
- COPD
- antagonizing M3 gives us bronchorelaxation
oxybutinin (ditropan)
anticholinergic
-used to help with bladder spasms and urinary retention issues
scopolamine (Maldemar)
anticholinergic
- used for motion sickness
- hits M1 and causes CNS depression
drug of choice for a cholinergic crisis
atropine or whatever anticholinergic is available
edrophinum
cholinergic drug used to discern between a cholinergic and myesthenia crisis
- if myesthenia crisis, the pt will get better (bc they had too little Ach)
- if its a cholinergic crisis, the pt won’t get better (they have too much Ach)
the 4 aunties
antipsychotics
antihistamine
antidepressant
anti-parkinsons
