I agree on marihuana, although BPD sufferers are very prone to substance abuse (I'm a living example), so I wouldn't really recommend it without proper research on its effects. For example there are mental illnesses like schizophrenia that get triggered by weed if you really have it (you don't get schizophrenia from weed out of nowhere). Same thing with kratom, one student was promoting it on our college dorm fb page, which triggered a debate and source posting about its effects and possible addiction/bad withdrawal risk. My bf bought it and even though many people have good experience (from the same source, I just want to accent that we didn't buy some shit), we felt sick to our stomachs even when we took the smallest recommended dosage. I felt only sick, like drinking too much coffee along with smoking too many cigarettes. My bf felt ill physically too, but he was alert and more receptive and he said that when he didn't feel the cramps in stomach so bad, he was able to study and learn with more interest and ease. It was still not worth repeating, though.