Opioid Analgesic Drugs Flashcards
What is allodynia?
pain in response to non-painful stimuli
Do analgesics treat pain?
no, they mask the pain -
where do opiates act in the pain pathway?
They promote the descending inhibitory pathways which inhibit the excitation of transmission neuron
They inhibit the neuropeptide release in the inflammatory pathway
they directly inhibit excitation of transmission neuron
Where do NSAIDs work in the pain pathway?
they inhibit inflammatory mediator release therefore reducing pain of inflammation
what is the difference between opiates and opioids?
opiate = naturally found in opium
opioid = synthetic opiate-like compound
what are the two types of opoid receptors?
- m (mu) - supraspinal analgesia - associated with pain modulation
- k (kappa) - spinal analgesia- associated with pain transmission
what is the effect of Morphine?
it is a mu, kappa, and delta receptor agonist
- leads to elevation of pain threshold without loss of consciousness
- given in many forms, half life of 3-4 hours
What are the side effects of morphine?
sedation/mental drowsiness
respiratory depression
nausea/vomiting
constipation- increased GIT muscle tone decreased propulsive moevements
miosis
tolerance/dependence
What is the clinical limitation of morphine?
gradual loss of effectiveness and dependence
what other drugs are opoid agonists?
codeine - also works as an antitussive
fentanyl - 100x more potent than morphine
oxycontin
tramadol
What is Targin?
an opiate that is a combination of oxycodone and naloxone - prevents constipation b/c maloxone is poorly absorbed. Prevents injecting the drug because if given IV the naloxone counteracts the oxycodone
What is the reversal drug for morphine overdose?
naloxone - note that the half life of it is shorter than morphine, so you require a repeat dose
what medication is most effective for neuropathic pain?
anticonvulsant and antidepressant medication is most effective
