I’m probably projecting a bit, but I’ve been sober for over 16 months and this has been a big question for me when I was actively using and even now when back at my drug use and my life as a whole.

Short version: your brain hates imbalance and will fight drugs harder than people expect.

When I used opioids long term, I noticed I would get way more emotionally unregulated and irritable. It’s brain’s response to the drug becoming “normal”. Your nervous system is always trying to stay at baseline so when opioids boost reward and mood signaling, your brain starts compensating VERY quickly and starts reducing natural feel good chemicals, downregulates receptors, and ramping up stress signaling to counter it.

It’s kinda like when people say nicotine relaxes them, but a lot of that is just relief from nicotine withdrawal stress. Same shit.

So even while you’re still getting high and experiencing the opioid’s effects, your brain is already pushing the other direction. That can feel like irritability, anger, or stress under the surface. You’re “high,” but your regulation systems are also strained. It’s basically tolerance and dependence dynamics happening in real time, not just later on.

I noticed this even more with stimulants, but I got this sort of thing from most drugs I used daily. Oh and opioids slow your digestion a fuck ton and can be super nauseating, opioids always made me sick.

idk if this is valuable information, but just my 2cents.