Yeah, you're right that most overdoses with meds like these don't usually lead to death.
Methotrexate can seriously mess you up, but it's slow as fuck and not guaranteed to kill. You'd need a big dose over time. It hits the liver, bone marrow, causes ulcers, infections. Prednisone is not really lethal in the short term. Might cause electrolyte issues, insomnia, or mood stuff, but you'd need crazy amounts to even risk death and even then it's unlikely. Duloxetine can cause serotonin syndrome, seizures, maybe coma at high doses but most people just get sick, end up in hospital, and recover. Pretty low fatality rate on its own. Pregabalin, and I'm speaking from experience here, will just sedate you, maybe make you blackout or act weird. Not very dangerous by itself unless you mix it with other downers (like benzos or alcohol). Again, not likely to kill you unless the dose is huuuuuge and mixed.
Paracetamol is the real danger. In high enough doses it can kill, but it's a slow and brutal death like we're talking 2–4 days of liver failure. People often feel better for a bit before they crash. If you don't die, you might end up with permanent liver damage. Hospitals can reverse it if they catch it early with a drug called NAC.
So yeah, a combo of these might put you in the hospital, maybe make you really sick, but none of them are guaranteed to do the job unless you take huge doses and even then, it's a gamble. The risk is you survive but end up worse off. Especially with paracetamol. Back when I was a teenager, I did this shit many times. I promise you it's not worth it. I know that's not what you want to hear but I swear to you that you will regret it. There are so many better options that don't require an insane risk like this.
