It's very easy to use...and is a wonderful tool!
I use mine to help keep my back from cramping while doing dishes and other housework.
I think it has to be perscribed...mine did, but that may just be so it would be covered by insurance. Have her ask her doctor or physical therapist about a "TENS UNIT"
I'll bet she could get a prescription for any pain help she wants - but I doubt she'd use it!