OPIODS Flashcards
What acts as a partial agonist? Why is that benificial?
Cuz ull get the analgesic effect, but w/ out alot if SE
Which one should be careful eith overdosing? Why
Buprenorphine lana its soo tightly bound to its receptor and so hard to dispace!
Which one is safe in renal impairment?
buprenorphine
Why can some ppl come and say oh codein wasnt that benefital? But some can say it was goals?
It depends on how much CYP 2D6 enzyme is expressed in their body, some have too much of it, some dont have alot
WHO analgesic ladder?
1) simple analgesia» paracetamol, NSAIDS
2) weak opiod» codeine
3) strong opiod» Morphine, fentanyl
Least lipophillic opiod
Morphine
CYP 2D6 is inhibited by ?
Flouxetine
When giving IV, Why should u not give nalxone as a bolus? but as a slow infusion
Bc if u give it as a bolus, it will competitivly antagonize R, & knock Morphine out of the way, u will then stop the bolus and the patient will leave the hospital with that morohine still circulating in their blood for longer than naloxone, and they rebind w/ the receptors> RESP DEPRRSSION.
BUT if u give short slow infusion, it was competitively antagonize that Morphine & reverse its effects very slowly, so the patient at least has time to metabolize that circulating morphine whilst that naloxone is still bound» u wont get crash
What is codeine?
Moderate agonist
Half life of fentanyl
6mins
Which one is good to give if polypharmacy? Elderly? Why?
Burpenorphine, less syncopal effects and fall effects
If u have patients whose taking loads of meds and r more likely to fall as SE, u don‘t wanna give them an opiod thats gunna make them fall more
Which drug doesn’t give u alot of SE? Why?
burprenorphine, once bound, only acts as a PARTIAL AGONIST, so u get the anelgesic effects but w/out the side effects
Duration of action of naloxone?
1/2-1 hr
Which one is less tho renally excreted than morphine?
Fentanyl
Codeine is converted to morphine via?
CYP 2D6
Mohim lalls
Which one is good for opiod addiction?
Buprenorphine
What is used for terminal illness?
Diamorphone» epidurally
Which one has low oral bioavailability? What does that mean
Naloxone, bc it has 1st pass effect in liver, only 2% is available in the circulation
Which one has a RAPID onset of action?
Naloxone
What is our main antagonist
Naloxone
Explain naloxone’s affinity to recepters in comparison to buprenorphine & morphine?
Has a greater affinity to Mu than morphine
But less that buprenorphine
Compared to morphine, is fentanyl more efficacious?potent?
Yes, has a high affinity for Mu R» more efficacious
No, less potent that Morphine
What do we give to treat opioid addiction? Why?
Buprenorphine
We can swap someone w/ their current opoiod that we think theyre abusing onto bup. So their pain is still well controlled, but we DONT have the risk of resp. depression. SO THEN we can titrate down that dose,
But its important to know that they may still get w/ drawl SE, bc theyre not getting that high response.
When giving it IV, Why cant we give naloxone as a bolus and must be given as a slow infusion?
It has a short half life, so if u give it as a bolus it will competitively antagonize those receptors & knock all morphine out if the way, u will then stop the bolus and they will get angry, cuz u reversed they high, they will walk out the hospital but that morphine is still circulating in their system for longer than naloxone & it will rebind to the recepters and u will get respiratory depression again & the patient will collapse.
Where as slow infusion, u will competitively antagonize that morphine & reverse the effects slowly & in a safe way, so that the patient has time to metabolize and eliminate that morphine, whilst the naloxone is still bound.
Which one should u be aware of giving it alongside another opioid? Why?
Buprenorphine, it easily displaces them
What can be given as a patch and lasts within a week, and slowly reduces its dose?
Buprenorohine
Has a ling half life
Name a competitive antagonist?
Naloxone
Which drug when given w/ another opioid, it displaces it?
Buprenorphine
Which one has an elimination via bilialry system
Buprenorohine» Biliary
Why is oral not the best route for naloxone?
Bc it has a very low oral bioavailability, even tho it 90% absorption in the gut, it doesnt matter lana most of it goes through 1st pass metabolism in the liver and only 3% is available in the circulation
What is our main competitive antagonist?
Naloxone
What disease should u be cautious in when giving morphine? Why?
Athamatics»
Cuz morohine causes Mast degranulation, massive histimine release> asthma attack
What is contraindicated it children below 12? Why?
Codeine, bc of the resp. Depression, children have massive tonsils and adenoids
Does it have a better or lower affinity to Mu R than morphine?
Greater affinity than Mor
But less than Bupr
How do u measure morphine in someone?
Measure it in urine
Whynis morphine given mainly IV?
Cuz first pass metabolism in GI > slow> so we give it IV
What do we give for diharrea why?
Morohine? Inhibits myenteric olexus & cause SM contraction
Do we give naloxone for opioid addiciton? Why?
No,
