Be careful with the alprazolam. I've done it before, but I found that if you sedate yourself too much then, thanks to the semi-stimulating nature of kratom, you can start to experience hypnagogic hallucination. I remember spending a good few hours trying to get to sleep after taking 5g of kratom and then taking 2mg of alprazolam on top of my usual 100mg of quetiapine. Within 15 minutes I was having full blown hallucinations (similar, to those I used to get before falling asleep, but more vivid) and started to suffer from severe anxiety (too sedating, my pulse dropped from my average of 90 BPM into the 40s and I began to panic). Of course I had the addiction of quetiapine into the mix, but I do think the alprazolam had something to do with the hallucinations.
Despite this, I've had no problems with taking alprazolam at the same time as taking kratom, and have only ever had bad experience when taking it a few hours AFTER.
Saying this I could be completely wrong, and the hallucinations may have just been a coincidental occurrence. But, it's just a warning.