Pharm 19 Flashcards
Identify where opioids act within the neurological pathway of pain transmission
- Opioids influence pain signals where peripheral nerve connects to the dorsal horn in the spine
- When activated opioid receptors generally create an inhibitory effect upon the neuron to which they are attached.
Acute pain
- 3-6 mos
- best treated with opioids
Chronic pain
- persist after normal healing process
- Fentanyl
Nociceptive pain
- Usually related to tissue damage, requires pain receptor activation
- normal opioid tx
Nociceptive pain: somatic
injury to body tissue, well localized
Nociceptive pain: Visceral
viscera mediated by stretch receptors
Neuropathic pain
- Abnormal neural activity secondary to disease, injury, or dysfunction of CNS.
- Tramadol
Cancer pain
-Best treated with opioids
List opioid drugs that are receptor agonist
Morphine
Hydromorphone
Codeine
Hydrocodone
Oxycodone
Meperidine (Demerol)
Fentanyl
Methadone
List opioid drugs that are receptor partial agonist
- Buprenophine
- Tramadol
List opioid drugs that are receptor antagonist
- Naloxone (Narcan)
- Naltrexone
- Methylnaltrexone
- Naloxegol
MC COD from opioid overdose
- Respiratory depression:
- Decreased sensitivity of chemoreceptors that sense high levels of CO2 in blood and decrease respiratory volume and rate
- Essentially brain stops realizing the pts need to breathe.
Mu receptors are found where
brainstem and medial thalamus
Kappa receptors are found where
limbic and other diencephalic areas.
Delta receptors are found where?
largely in the brain
PK of opioids
- PK properties determine their analgesic and side effects
- bioavailability is about 75-85%
- highly water soluble, rapid onset of action
- duration of action if related to their t 1/2
- flow dependent hepatic clearance