Opioids

Question 1

what are the four steps in feeling pain?

Answer 1

transduction
transmission
modulation
perception

Question 2

what two places in four steps of feeling pain do opioids work?

Answer 2

modulation and transmission

Question 3

where doe descending and ascneding pain sensations summate in the SC?

Answer 3

dorsal horn…good spot for opioid action

Question 4

where else are mu opioid receptors found in body other than brain and SC?

Answer 4

peripheral nociceptor neurons and GI

Question 5

name the full agonists opioids

Answer 5

codeine
morphine
hydrocodone
oxycodone
heroin
methadone
meperidine
fentanyl 
remifentanil 
carfentanil

Question 6

what is most potent full agonist?

Answer 6

carfentanil

Question 7

what opioid is used to compare potency?

Answer 7

morphine set as 1

Question 8

what are oral opiods subject to?

Answer 8

first pass effect

Question 9

where are opioids mainly cleared

Answer 9

kidneys

Question 10

what are opiods broken down into before clearance?

Answer 10

polar metabolites

Question 11

what three drugs are broken down into more potent drugs?

Answer 11

codeine
hydrocodone
oxycodone

Question 12

what is secondary effect of increased morphine metabolites in system?

Answer 12

seizures

Question 13

what is codeine broken down into?

Answer 13

morphine

Question 14

what is hydrocodone broken down into?

Answer 14

hydromorphone

Question 15

what is oxycodone broken down into?

Answer 15

oxymorphone

Question 16

what is secondary effect of increased hydromorhpone metabolites in system?

Answer 16

neurotoxicity

Question 17

name the foursafe opioids to give with renal failure

Answer 17

fentanyl
hydromorhpone
methadone
buprenorphine

Question 18

what do opioids do to pre synaptic neuron in ascending path?

Answer 18

inhibit voltage gates Ca2+ entry

Question 19

what do opioids do to post synaptic neuron in ascending path?

Answer 19

increase K+ efflux…hyperpolarize cell

Question 20

what is opioids MoA in descending path?

Answer 20

inhibits GABA so GABA cannot inhibit the pathway anymore

Question 21

how do opioids inhibit GABA in descending path?

Answer 21

inhib Ca2+ influx in presynaptic terminal to release GABA…so decreases GABA release

Question 22

what are three adverse affects with acut opioid use?

Answer 22

respiratory depression
constipation
sedation

Question 23

what are three adverse opioid effects with chronic use?

Answer 23

hyperalgesia
tolerance
withdrawal

Question 24

where are there mu opioid receptors that contribute to respiratory depression?

Answer 24

respiratory center of the pons

Question 25

how do opioids cause constipation?

Answer 25

target mu opioid receptors in GI and lead to less contraction of SM there

Question 26

what opiods is used to treat diarrhea?

Answer 26

fentanyl and eluxadoline

Question 27

what drug class treats opioid induced constipation?

Answer 27

PAMORAs

Question 28

what are PAMORAS

Answer 28

peripherally acting mu opiod receptor antagonsits

Question 29

what is the PAMORA to know?

Answer 29

methylnaltrexone

Question 30

if patient builds up tolerance to opioid what can you do? but what can be issue with this?

Answer 30

can switch to other opioid...but often has cross tolerance

Question 31

how do opioids lead to euphoria/addiction?

Answer 31

stimulate the mesolimbic dopaminergic pathway by inhibiting GABA release so dopamine is uninhibited

Question 32

when is peak opioid withdrawal?

Answer 32

72 hours after last dose

Question 33

what are symptoms of opioid withdrawal?

Answer 33

chills, fever, body ache, msucle pain, nausea, dilated pupils

Question 34

what type of opioid is methadone?

Answer 34

full agonist

Question 35

what is unique about methadone in treating opioid addiction?

Answer 35

has very long halflife and can satisfy cravings...and does not lead to withdrawal symptoms

Question 36

what class of opioids is buprenorphine?

Answer 36

partial agonist

Question 37

how does buprenorphine treat addiction?

Answer 37

partially substitutes full agonist opiods...so reduces withdrawal symptoms and eases detox

Question 38

what two meds are used in acute overdose? why?

Answer 38

naloxone and naltrexone ...because they are antagonist and inverse agonist

Question 39

what does it mean for naloxone/naltrexone to be inverse agonist?

Answer 39

take away the basal level of firing of the mu opioid receptor

Question 40

what does it mean for naloxone/naltrexone to be antagonist?

Answer 40

inhibit binding of other opioids to mu receptor

Question 41

what is suboxone?

Answer 41

combo of buprenorphine and naloxone