I see what you're saying. It's kind of like having two agents that can be volatile when mixed in combination with the wrong things. Our brains have become one of those agents. The other can be certain stresses, chemicals such as meds, or noises (that also does it for me).
The medicine that does it the worst for me is percocet. It took quite a while for me to figure out. Every day while I was in rehab, my therapist said I should take the percocet 30mins before coming to therapy. Being a good patient, I would do that. Pretty much everyday I ended up in an emotional blow up in the therapy session that I seemed to have practically no control over-- even though I swore to myself it wouldn't happen that day. I would be crying uncontrollably or cursing someone out or threatening someone. Invariably, by evening I would be in my room feeling like I had just become Charles Manson. By night I was fine. On the weekends I didn't have therapy scheduled, so I didn't take the percocet unless I had to. My docs just chalked it up to the brain injury but I felt like it was due to the meds because it was far too scheduled like the meds. Outbursts from brain injury don't follow a schedule typically. So, I stopped the percs for a while and the extreme episodes stopped.
I have been given percocet since on trips to the ER(didn't think to ask what I was given until after they were down), same old same old. I don't know why they do that to me. I had those before the injury without such interactions.