I have benign low bp, typically lowest upon waking up (90's/50's). at times i feel shaky/weak from it. anything to help raise it quickly in mornings?

Your question raises: many more questions such as medications you are taking, what is your pulse rate when you feel "shakey", how long does the symptom last, does it happen throughout the day? It is too hard to answer with any degree of accuracy in this forum. Perhaps the paid site where you could talk to one of the doctors to get these questions, and more answered. Or you could consult your PCP.