narcotic analgesics Flashcards
how does opioid analgesia work on endogenous mechanisms?
inhibit the propagation of pain signals
alter the emotional perception of pain
elevate the pain threshold
sites of opioid receptors regulating pain (3)
peripheral nociceptive terminals (peripheral analgesia)
spine (spinal analgesia)
brain (supra spinal analgesia)
3 major opioid receptor types
Mu
Delta
Kappa
elderly patients usually require a ___ dose to achieve effective pain relief than younger patients
lower
neuropathic pain usually requires a ____ dose than nociceptive pain
higher
_____ doses are usually required for continuous maintenance of pain relief
lower
drugs for analgesia (3)
codeine morphine pethidine
drugs for anaesthetic adjuvant
fentanyl
drugs for cough suppression
codeine
antidiarrhoeal drug
diphenoxylate
name the 4 strong opioid agonists
morphine
methadone
fentanyl
pethidine
caution when using morphine, methadone and fentanyl
high addiction potential
methadone is a __-acting while fentanyl is ____ acting
long, short
Name 2 moderate opioid agonists
Codeine
Tramadol
Codeine is a weak __ and __ agonist
Mu and delta
Tramadol is a….
Weak inhibitor of 5-HT and NA reuptake
How does respiratory depression occur
Actions in the nucleus tracts solitarius and nucleus ambiguus reduce responses to CO2 and H+ And suppress voluntary breathing
8 common ADR of opioids
Nausea Vomiting Drowsiness Constipation Miosis Urinary retention Postural hypotension Immunosuppressant in long term use
Morphine specific ADR
Histamine release
- urticaria and itching
- brinchiconstriction
- hypotension due to vasodilation
Use with caution in asthmatics
Opioid antagonist (3)
Naloxone
Naltrexone
Nalmefene
Naloxone is ___ acting (usually administered___)
Short
IV
Naltrexone is ___ acting usually administered ____
Long
Orally
Nalmefene is __ acting and usually administered ___
Long
IV
