Opiods

Question 1

what is an opiod?

Answer 1

any substance (natural or synthetic) that
produces morphine like effects which are
blocked by a morphine antagonist
(e.g. naloxone)

Question 2

name some strong opiods

Answer 2

morphine 
diamorphine 
oxycodone
fentanyl 
pethidine
remifentanil 
methadone

Question 3

name some weak opiods

Answer 3

codeine
dihydrocodein
tramadol
loperamide

Question 4

what is the oral bioavailability of morphine

Answer 4

30%

Question 5

what is the oral bioavailability of oxycodone

Answer 5

70%

Question 6

what are the sites of action of opiod receptors

Answer 6

Mu
kappa
delta
nociception opiod receptor

the most important one for analgesia is Mu

Question 7

what is the antagonist of opioids

Answer 7

naloxone

Question 8

what is the parenteral dose of morphine

Answer 8

10mg

Question 9

what is the standard oral dose of morphine

Answer 9

30 mg

Question 10

what is step 1 of the analgaesic ladder

Answer 10

NSAIDS

Question 11

what is step 2 of the analgaesic ladder

Answer 11

weak opiods plus NSAID

+- adjuvant

Question 12

what is step 3 of the analgaesic ladder

Answer 12

strong opioids plus NSAID
oral/transdermal patch

e.g. methadone

Question 13

what is step 4 of the analgaesic ladder

Answer 13

nerve block, epidural, PCA pump, spinal stimulators

plus NSAID

Question 14

what are the principles of pain medication administration

Answer 14

drug by mouth if possible

give the drug ‘by the clock’ i.e. give it regularly

have a dose ready for breakthrough pain

go up the ladder in a stepwise fashion (adding in on top)

personalize to the patient

anticipate side effects of the drug

Question 15

what is opium

Answer 15

extract from poppy

Question 16

what is an opiate

Answer 16

naturally occurring opioid

Question 17

what should you consider when thinking about drugs

Answer 17

what class is it
how is it given 
what is the MOA
what are its uses
how is it metabolized
what are the effects on body systems
is there anything else to know 
what is the duration of action 
what is the potency

Question 18

what is the ceiling effect of weak opioids

Answer 18

increasing the dose does not improve analgesic effect

Question 19

what is a problem with using morphine

Answer 19

low bioavailability so usually not given orally

Question 20

what is diamorphine

Answer 20

heroin

crosses the BBB so open to abuse

Question 21

what are effects of loperamide (immodium)

Answer 21

very low oral bioavailability
used as a constipator
is an opioid

Question 22

what is PCA

Answer 22

patient controlled analgaesia

Question 23

what are the endogenous opioids

Answer 23

endorphins, encephalins and dynorphins

Question 24

how do opioids affect the pupils

Answer 24

pinpoint pupils

Question 25

what are some side effects of opioids

Answer 25

``` euphoria sedation decreases respiratory rate (should not fall below 8 per minute) stops people coughing (anti tussive) morphine: release of histamine (bronchoconstriction and vasodilation) be careful in asthmatics decreases heart rate affects SAN and sympathetic drive constipation- so prescribe a laxative/ stool softener (myenteric plexus) nausea and vomiting (CTZ, vestibular apparatus, slow gut motility) urticaria, itch urinary retention may impact kidneys increased ADH decreases immunity ```

Question 26

why might morphine cause a decrease in blood pressure

Answer 26

histamine combined with decrease sympathetic innervation to the heart

Question 27

what is naltrexone

Answer 27

reverses the effects of opioids and used in opioid dependence

Question 28

what is methadone

Answer 28

long acting opioid

Question 29

what is a common side effect of methadone

Answer 29

tooth decay dries up secretions, gives munchies and is administered in a thick glucose syrup

Question 30

what are the features of a controlled drug prescription

Answer 30

``` specify the form of the preparation (tabs or caps) specify the dose to be taken give the strength of the preparation enter the total quantity in both words and figures signed and dated by prescriber ```