Affinity variances

[Tuvya]

Am I correct on this... and what exactly does it mean that suboxone has a higher affinity level of opiates than street heroin and therefore has a greater likelihood of breaking through an opiate antagonist than heroin? Does this mean suboxone has a greater opiate potency than heroin?

 

[Psychonauticunt]

Am I correct on this... and what exactly does it mean that suboxone has a higher affinity level of opiates than street heroin and therefore has a greater likelihood of breaking through an opiate antagonist than heroin? Does this mean suboxone has a greater opiate potency than heroin?

It has a higher affinity to the relevant opioid receptors in the brain. That has nothing to do with potency, but with how strongly it binds to receptors. Buprenorphine (the main active ingredient in Suboxone) has a higher binding affinity than just about all other opioids; this basically means that the brain 'prefers' buprenorphine when it is present, and it will displace or block other opioids from attaching to receptors.

Buprenorphine is more potent than heroin, but potency has to do with the active dose, which for buprenorphine is very small. Heroin is a full agonist while buprenorphine is a partial agonist, so heroin exerts more powerful effects.

 

[Snake_Eyes]

What about bupe to methadone?

 

[Psychonauticunt]

What about bupe to methadone?

Buprenorphine has the higher affinity. The only opioid with higher binding affinity that I can think of is sufentanil (an analogue of fentanyl, about 10x more potent) - it's sometimes used for that reason to provide pain relief for individuals that are on high-dose buprenorphine for maintenance - any other analgesic would be blocked off by the bupe. Methadone has relatively high affinity but buprenorphine is almost unmatched.

 

[Snake_Eyes]

Thanks but if bupe has such a high binding affinity then why is it used for people with weaker opiate addiction and methadone is the go to for heroin and other heavy weights?

 

[Larc]

Not sure what you base your comment off of snake eyes.

Methadone is more common because of its availabilty. This has nothing towith how bad ones habit is.

 

[Psychonauticunt]

Thanks but if bupe has such a high binding affinity then why is it used for people with weaker opiate addiction and methadone is the go to for heroin and other heavy weights?

That's not necessarily the case. Plenty of people take buprenorphine for heroin and other heavyweights, and as far as I know very few people take any sort of therapeutic replacement drug for weaker opioids. Waning yourself off tramadol using bupe?

Binding affinity has nothing to do with how 'strong' the opioid is. One reason you might give someone with a high tolerance to strong opioids methadone instead of buprenorphine is that methadone is a full agonist, like heroin/morphine/oxycodone/etc, while buprenorphine is a partial agonist. If you are highly tolerant to strong opioids, buprenorphine binds very strongly to a receptor that is accustomed to having a stronger drug, and you may still experience some withdrawals. With methadone this is not the case.

Methadone may also be chosen simply because it's cheaper than buprenorphine. Buprenorphine, on the other hand, as a partial agonist is less dangerous in overdose and less sedating in general, so that may be preferable.

 

[Snake_Eyes]

Makes sense.

By weaker addictions I meant people who are addicted to like high doses of hydrocodone or moderately high amounts of oxycodone for example.