I use my heating pad on low on my feet when my legs and feet spasm. It helps slightly, enough so I can rest. My neuro actually got an exception for me through my insurance for Cambia for my migraines. Cambia is diclofenac powder, diclofenac is the active ingredient in Voltaren...maybe that is why my spasms haven't been quite as bad, and it helps relieve my migraine for a couple of hours.