I too suffer from horrific muscle spasms in my back and legs. I started with Flexeril and then Robaxin, but with 6 months neither helped. I was then switched to Baclofen, which is one of the gold standards – along with Zanaflex – for muscle spasms and spasticity. Unfortunately, within 8 months of using oral Baclofen (which does a wonderful job) I went from using 10 mgs to 130 mgs a day. The side effects became a problem and I had no choice but to have a Baclofen pump implanted.
You might want to ask your physician if you are a candidate for either oral Baclofen or Zanaflex, both are muscle relaxants, but not in the benzo category.
I know what you are going thru – and I am so sorry.