Unconverted Codeine

[Gaz_hmmmm]

Only 10% of codeine is converted to morphine in the liver and brain, what my question is of the 90% of the codeine left is all of this passed out as waste or does codeine actually have any affect by itself?

 

[fastandbulbous]

Ends up as norcodeine, codeine-6-glucuronide. On its own it's a week mu agonist that's not really that hot at all (it's pretty crap in people with a CYP2D6 deficiency)

 

[BilZ0r]

norcodeine is the big one though... There affinitys are
Codeine 248nM
Norcodeine 266nM
Codeine-6-glucuronide 238nM
Morphine 1nM