fentanyl is a relatively exotic pharmaceutical and is not widely prescribed except in very serious or unusual circumstances. i have read a good deal about production shifting from china to mexico in the last few years with china shifting more toward precursors following a ccp crackdown, but what i've read today suggests that the bulk is still produced and finished in china for export, with india's chemical industry as a potential major new source. i found this collection enlightening: https://insightcrime.org/investigations/mexico-deadly-rise-f...

i have very strong certainty that illicit fentanyl production outweighs legitimate simply due to the fact that it is not widely prescribed while it is crowding out the entire hard drug market in the US, but illicit fent still appears to mostly be produced by china for now.