Opioid Analgesia Flashcards
(27 cards)
Opiate
Drug derived from opium
Morphine, codeine, diamorphine
Opium
Derived from the Greek word ‘Opus’
The extract from an opium plant
Opioid
Opioid receptor agonists
How many alkaloids in Opium?
> 20
Name the 3 opioid subtypes
Mu
Papa
Delta
What is morphine metabolised to?
M3G (neuro- excitory effects)
M6G (additional analgesic effects)
What are the slow & immediate release morphines?
Slow = MST
Immediate = Oramorph
What’s more lipid soluble: Diamorphine or morphine?
Diamorphine
What is diamorphine (heroin) metabolised to?
6-monoacetylmorphine (6MAM)
Morphine
What is co-codamol?
Paracetamol & codeine
What is cytochrome P450?
An enzyme
Found in liver
Metabolises things
…..
Name an ‘atypical opioid’
Tramadol
Why is tramadol poorly tolerated in the elderly?
It acts on central receptors
GABA, seroternergic, catecholamines
They get agitated
Name a weak opioid
Codeine
What opioid receptors does oxycodone act on?
Mu & kappa
Bioavailability
When drug enters body how much is available to use?
What is the oral bioavailability if morphine?
Between 30-70%
Name the advantage of oxycodone
It has a high oral bioavailability
What receptor does methadone act on?
Mu
When is methadone used?
In opioid addiction (long half life) and neuropathic pain
Where is methadone metabolised?
The liver
Excreted in faeces
What opioid agonist can only be injected, crosses te BB barrier very quickly, and is 80✖️ more potent than morphine?
Fentanyl
What will reduce chance of heroin overdose & taken sublingually in opioid addiction?
Buprenorphine
Name 4 side effects of opioids
Nausea & Vomiting (CTZ)
Sedation
Constipation
Hypotension
