Opioids 1 & 2 Flashcards
What is an opioid?
A term to describe compounds both natural and synthetic that have properties similar to opium or morphine. Catch all term for anything thats synthetic or natural basically.
What is an opiate?
Refers to only natural occurring compounds
What are opioids and opiates clinical function?
Powerful analgesics, have dramatic effect of the affective compound of pain (anxiety, worry, uneasiness). Decreases pain signals, but also has a psychological effect, seems to distance you from the pain. And causes sleep (narcotic)
What is morphine?
Gold standard for pain killers, prescription only in Canada. Those using for pain do not typically become addicted, patterns of high use with pain, will decrease dose when pain diminishes
Where do natural opioids come from?
Papaver somniferu poppy, opium is in the sap of the plant. But the plant only makes drug 10 days of its life cycle
What is opium?
A mixture of narcotic and non narcotic alkaloids.
Narcotic components are morphine and codeine (codeine is converted to morphine in liver)
What is heroin?
It is semi synthetic opioid, in 1874 two acetyl groups were added to morphine making Diacetylmorphine
What does adding the two acetyl groups to morphine do? (to make heroin)
Makes its 10 times more lipid soluble than morphine and therefore more potent. Gets to brain faster and in higher concentrations. The two acetyl groups are metabolically removed once in the brain and then it can bind to the receptors
Once in the brain, when the acetyl groups are removed from heroin, what is produced?
6-monoacetyl-morphine (6-MAM) and 3-monoacetylmorphine (3-MAM) are produced. 6-MAM binds to mu receptor and is psychoactive. Both are then converted into morphine.
How can you test for heroin use?
6-MAM is only present in heroin users
What is Krokodil?
Is is desomorphine. Originated in Russia, contains codeine, red phosphorous, gasoline, iodine and hydrochloric acid. Its more potent than morphine because it more lipophilic. The final product isn’t filtered so it contains a bunch of toxins still and causes immediate damage to blood vessel, muscle and bones. It produces abscesses, gangrene, necrosis…
If you mix oxycodone with acetaminophen, what do you get?
Percocets
If you mix oxycodone with aspirin, what do you get?
Percodan
What is oxycodone?
semi synthetic opioid, one of the most abused prescription analgesics
How is oxycodone different from oxycontin?
Oxycontin is a table that contains many times the amount of oxycodone, but it was designed as a time-release formula, so it lasts all day. It has a higher dose so it has a very high abuse rate
How was oxycontin abuse curved? What drug did they replace it with?
They formulated a version of slow release oxycodone, OxyNeo, that contains polyethylene oxide so that if the user crushes it into powder to snort, it forms a yummy gel when exposed to fluid–> making it difficult to abuse. Theres evidence that this abuse has decreased, but shows that abusers are switching back to heroin and fentanyl
What is fentanyl?
Used primarily as a surgical anesthetic and analgesic, but found in lollipops and skin patches to control pain. It is 100x more potent than morphine, 40-50x more potent than heroin due to lipophilicity. It is fast acting with short duration
List some of the general opioid use effects
Intense euphoria, drowsiness, mental clouding, sleep sensation. Analgesia may last 3-5 hours, but in some people you see a stimulatory effect
List some of the physiological effects of opioid use:
-constriction of pupils due to agonist effects on mu and kappa receptors in oculomotor nucleus, nausea and vomiting, lowering of BP, vasodilation may lead to profuse sweating, histamine release- hypotension, bronchoconstriction, itching
What are most deaths from opioid use caused by?
Asphyxiation, opioids cause respiratory depression associated with decrease in sensitivity to arterial CO2 and inhibition of respiratory rhythm
Explain smoking heroin as a route of administration:
Pure heroin is heated on foil until it vaporizes, 17-63% of heated heroin is vaporized. A medical issue with smoking heroin is destruction of white matter (leukoencephalopathy)
Explain Iv injecting as a route of administration (heroin)
Heroin is mixed with water and sometimes lemon juice to help dissolve heroin. Heat up mixture in a spoon to body temp.
What are chippers?
Occasional users, proves people do not become instantly addicted
What are needle freaks?
They associate IV injection with the drug and start to enjoy the act of injection almost more than the drug itself
What are the four families for endogenous opioid like substances in our body? And what do they all have in common?
Enkephalins (delta), endorphins (mu), endomorphins (mu) and dynorphins (kappa). and they all have tyrosine amino acid at the end of their chain. These can all function as NT, neurohormones and neuromodulators
Mu, Kappa and Delta receptors probably exist as dimers in a receptor, what is each of their function?
Mu- euphoria, respiratory depression, analgesia, dependence
Kappa- dysphoria, some analgesic effects
Delta- some analgesic effects
What happens when opioid receptors are activated? Describe the series of events that happens
When activated, all three inhibit adenylate cyclase to reduce cAMP levels.
Presynaptically: inhibits Ca2+ influx, thereby inhibiting NT release
Postsynaptically: Enhances K+ flow outwards, which hyper polarizes the membrane
= decreases neuronal excitability at cellular level.
But.. they all increase dopamine release at the NA through disinhibition
If opioids have an inhibitory effect, why is there in increase in the reward pathway?
Usually the mu receptor activate GABA to prevent dopamine being released, but when opioids are present, it inhibits the GABA release, so nothing it stopping dopamine from being released, and it accumulates in the synapse
