Replies to post #15079 on RespireRx Pharmaceuticals Inc (RSPI)

[neuroinv]

Enemem:

Interesting find. However, in the article itself, the authors write:
<<It is noteworthy that the delayed tolerance development was seen only for the analgesic effect of tapentadol; tolerance development for the respiratory depressant effect was not delayed compared with morphine>>.

Thus, in spite of the in vitro pre-Botzinger effects of norepinephrine, it doesn't look like in vivo, NE reuptake inhibition has a different effect on respiratory function (i.e. the inference appears to be that if development of tolerance to RD effect is not changed compared to opioid, that the RD threshold is the same). Tapentadol has a better GI side effect profile, but it looks like RD risk is the same--and while the authors highlight the former, I see no reference to any change in RD risk, and I doubt that there is any.

NeuroInvestment