Ugh...I have been dealing with these lately mostly in my back and they tend to last the whole day. The first time I wasn't sure and tried a bunch of different things but the best thing ended up being a hot bath followed by leaning on my electric heating pad all day. When I did this last time starting in the morning and using the heating pad all day it helped a lot. The spasms were still there but at least I felt like I could breathe without wanting to die...it really took the edge off. I also tried using a lidocaine patch, voltaren gel, stick on heating pad...none of those seemed to work at all. But the hot bath right away followed up with putting the electric heating pad behind my back while sitting seemed to at least take the edge off. Still was bad though and I was pretty useless all day.