week 3: CNS continued...drugs affecting the CNS Flashcards
drugs given in the CNS are
centrally active drugs
what are types of CNS depressants
anti-psychotics
opioid analgesics
sedative-hypnotics
why are CNS stimulants not used as often
they are less useful therapeutically
define pain
subjective experience-unpleasant
define pain threshold
level of stimulus that results in the perception of pain
define pain tolerance
level of pain endured without interfering with normal functioning
define analgesic
drug that relieves pain without causing LOC
pain classifications-by onset and duration
chronic
acute
pain classifications- by source
somatic
visceral
superficial
vascular
referred
neuropathic
phantom
cancer
psychogenic
central
when people OD what do they die of
respiratory depression
opioids-mechanism of action: agonist…what does it bind to and causes what and an example
-bind to opioid receptor in the brain
- cause analgesic response
ex. morphine sulfate
opioids-mechanism of action: partial agonist, binds to, causes what, example
-pain receptor
- cause limited actions
- pentazocine/talwin
opioids-mechanism of action: antagonist…what does it do, binds where, what is it known as, examples
-reverse the effects of other opioid agents
- binds to receptor and has no action
- body’s own ‘endorphins’
-ex. naloxone
TYPES OF OPIOID ANALGESICS
-codeine sulfate
- meperidine hydrochloride (demerol)
- methadone hydrochloride
- morphine sulfate
- propoxyphene hydrocloride (darvon)
why use opioid analgesics
relieve moderate to severe pain
- cough centre supression
- antidiarrheal
- part of balanced anesthesia
contraindications of opioid analgesics
- known drug allergy
- severe asthma or respiratory insufficiency
- elevated intracranial pressure
- pregnancy
opioid analgesics: side effects
-urinary retention
- diaphoresis and flushing
- pupillary constriction (miosis)
- constipation
- itching (pruritis)
-euphoria
- cns depression
- N&V (nausea and vomiting)
- respiratory depression
opioids: special concerns…define opioid tolerance
larger doses required to maintain analgesia-from chronic use
opioids: special concerns…define opioid physical dependence
physical adaptation to the presence of an opioid
opioids: special concerns…define opioid psychological dependence
compulsive use-craving and need- for effects other than pain relief
-addiction
what is something that is expected with long term use of opioids
opioid tolerance and physical dependence
signs if someone took an opioid vs someone who took a stimulant
opioid: pupils small
stimulant: pupils big
opioid analgesics…nursing implications to be aware of
respiratory status…monitor for respiratory depression
- no one dies from drug withdrawal
- oral to iv form…decrease the dose bc no first pass effect
When is morphine commonly used
works best on chest pain
- for severe chest pain…give them morphine from iv
