It doesn’t stop OD, but it reduces OD because it eliminates one type of very common OD: people taking seemingly safe quantities of drugs that have been laced with fentanyl.
Statistics are fuzzy on this, because you can’t always positively determine intent, to separate accidental overdose from suicide.
The number of overdose deaths are spiking, driven by fentanyl. That is 100% fact based.
Now you have to make a qualitative judgement: I think most ODs are accidental when this is studied. Did a whole shitload of drug users just become unusually suicidal? I would say it’s safer to assume “no” unless you see evidence to the contrary.
If you have good opioids in hand then there's no need to buy opioids of uncertain strength from dubious sources. Thus your dosage is more controllable.
If your supply is reliable then there is no seesaw of deprivation when you're out and overindulgence when you're flush.
For further data, apply the same logic that keeps people from oding on alchohol.
I think clinics with pills are the best compromise here. It would be insane to have otc access to opioids. It's not like addicts live normal lives and OD'ing is the only danger.
Is that the metric we care about? Wouldn't "amount of people dying of opiods" and "amount of people having their lives ruined by opiods" be better ones?
Th way I see it, alcohol issues wouldn't be reduced if you made it illegal and less people drank it, but now people are drinking unregulated moonshine that makes them blind or kills them because it contains methanol and isopropanol.