It was withdrawn for sometimes being metabolized into another, toxic and carcenogenic, molecule.
It's a paradox no?
Paracetamol is only the presumed only active metabolite, and that is why paracetamol rapidly replaced phenacetin.
There is a quirk though, phenacetin actually delivers paracetamol to your brain and spine (where it primarily reduces pain) faster than an oral dose of paracetamol.
Similarly IV paracetamol is far more effective that oral paracetamol.
Phenacetin was also considered mildly addictive, and induced a gentle euphoria and then sedation.(We still see sedation after paracetamol in children and the elderly). But general use we don't see these effects in paracetamol, why did phenacetin do this more effectively? Probably the higher peak levels around nerve endings.
These effects are both wanting of an explanation of phenacetin is just paracetamol and directly analegisic.
[0] https://web.archive.org/web/20240721144157/http://www.eviden...
I guess it tracks with personal experience. I find Paracetamol is OK for fevers/generic cold symptoms but absolutely useless for a headache, Ibuprofen is the only thing that shifts them.
Well it's the only thing that shifts them now I'm in a country where I can't buy soluble aspirin and codeine OTC.
What annoys me is that so many people have your experience and are effectively gaslit about the fact it seems to often perform so poorly.