Can I take muscle relaxers after inner thigh lift surgery for back pain?

I am 9 days out from an inner thigh lift with incision in the groin area. I also had lipo on my outer thighs. All is well but I am having a lot of back pain from sitting and lying around so much. Would it be ok to take a muscle relaxer such as Flexeril or Zanaflex. I haven't been taking any more pain meds for about 3 days now. I am having trouble sleeping which is making the healing process much more difficult.