Opioid analgesica Flashcards
morphine analogues:
structure similar to morphine
synthetics:
unrelated structure to morphine
morphine-like alkaloids:
morphine
diamorphine
codeine
heroin vs morphine
both strong analgesic
more lipid soluble
shorter duration
codeine vs morphine
less analgesia
NSAID
antitussive
codeine as an antitussive replaced with…
dextropmethorphran
synthetic opiates:
benzamorphanes
phenylpiperidine
thebaine
pethidine vs morphine
restlessness
antiuscarinic
shorter duration of action
fentanyl vs morphine
80-100 x more potent than morphine
rapid onset
short duration
anesthesia
the activity of tramadol:
weak mu agonist
serotonin and norepinephrine reabsorption inhibitor
moderate to severe pain
both tramadol and codeine are….
partial agonist
explanation of tramadol psychotropic effects:
it is an serotonin and norepinephrine reabsorption inhibitor
methadone receptor selectivity
mu
methadone vs morphine
slow acting
longer duration of action
less problems with withdrawal
given orally
methadone applications:
wean off heroin and morphine addiction
pharmacokinetics of Heroin vs methadone
methadone plasma concentration doesn’t induce euphoria or withdrawal
loperamide receptor selectivity
mu
loperamide effects:
decreases GIT motility
suppresses gastocolic reflex
why does loperamide have reduced circulation?
P-glycoprotein efflux
loperamide permeability:
poor blood-brain barrier permeability and so no analgesic activity/ euphoria
loperamide uses:
anti-diarrhea
full agonists:
morphine
heroin
agonist-antagonists
cyclazocine
pentazocine
antagonists
naloxone
naltrexone
partial agonists:
partial effiacy, regarldess of max concntration
codeine
agonist and antagonist
different towards different receptors
different depending on the concentration
antagonists
competitive or non-competitive
pentazocine selectivity:
agonist at K receptors
weak antagonist at mu and delta
pentazocine at low doses
similar to morphine
pentazocine at high doses:
dysphoria
respiratory depression
decreases GIT activity
hallucinations
nightmares
