You are mistaken.
Phenobarb (gotta get it IV, btw, preferably while in restraints and your head in a styrofoam helmet. No spitgaurd at least) is a barbiturate, messier than benzos, works the same way as alcohol. No direct dopamine or serotonin, just a happy downer.
Phenylethylamines look like adrenaline and dopamine. Too much can blow up your heart. Not meth though, that's totally safe.
Tryptamines are safer because they look more like melatonin than adrenaline (but could still kill you other ways). They don't directly do anything with dopamine.
Dopamine receptor agonists would be things like cocaine and meth, which might help your opiate problem, true.
For trauma they use ketamine while they cut you while awake. The doctors don't want to suppress your breathing further with opiates, so they give ketamine. You still hurt real bad, you just don't remember it very well. That one works on NMDA (glutamate) receptors.
Yeah, SSRIs are fading out for a lot of uses I think (I'm not a shrink and really have no idea, but it's in the air). Some serotonin receptor agonists and antagonists are antidepressants. Other serotonin receptor agonists are LSD and shrooms. It's tricky.