Opiates and Opioid Drugs Flashcards
Nociception
- the ability to perceive or sense pain
- opiates produce “anti-nociception”
Analgesia
Absence of pain in response to stimuli that are normallly painful without loss of consciousness
Hyperalgesia
Extreme responsiveness to stimuli that are usually only modestly painful
Allodynia
Pain caused by a stimulus that would not normally provoke pain
What do analgesics do
Drugs that block the formation, impulse transmission in sensory nerves transmission in spinal/supraspinal pathways or central perception of pain
Opium
Dried extract of the milky of seeds of the opium poppy plant
Opiates
Naturally occuring alkaloids in opium plant seeds.
Opioids
Drugs that mimic of block the actions of morphine at opioid receptors
Drug classes are based upon
Abuse potential and medical utility
Opioid receptors
Mu, kappa, delta
-most receptors are stimulated by morphine (agonist) and blocked by naloxone (antagonist)
Morphine receptor class
Mu, delta, kappa agonist
Fentany receptor class
My agonist
Butorphanol receptor class
Partial mu agonist, kappa agonist
Naloxone receptor class
Mu, delta, kappa antagonist
Where are the highest densities of opioid receptors
Brain, spinal cord, GI tract
Define mixed agonist antagonist
A drug that stimulates some receptor subtypes, but antagonizes other subtypes of the same receptor family
Partial agonist
Drug that produces a submaximal effect, even at maximally effective concentrations
Endogenous opioid peptides
A diverse group of peptides that are most prevalent in CNS and GI tissues
-considered to be the primary endogenous substances that activate opioid receptors
Roles of endogenous opioid peptides
Known to be released in response to painful stimuli, prolonged intense physical exertion and fight or flight reponse
Pharmacological actions of opioids
- opioids exert diverse and drug-specific actions with marked species dependent effects
- opioids depress CNS, GI, and Cv systems
