I used to take cyclobenzaprin for muscle spasms at night. This made me groggy the next day.
Finally my arthritis Dr. prescribed gabapentin. What a relief! I started with 100mg. Then I went to 200 mg. No more spasms and cramping. I went online and did some research and come to find out it is recommended for PPS.
Give it a try.
One thing to consider if you have leg cramps is your iron level. PPSers tend to have low iron levels, due to rhabdo, and this can cause "restless leg syndrome".
If you suspect this, though, first have your doc check your FERRITIN level (a type of iron), since supplementing iron levels when they're not low can lead to other problems.