I had Botox but the aim of mine was to try and reduce the length of my fissure before I had LIS as it was two inches so my surgeon couldn't cut the full length.
I loved my Botox it kicked in quite quick, it stopped my spasms from day one and the burning and stinging went after about 2/4 weeks. It lasted a good 12/16 weeks for me. I know a couple of members on here have been healed by Botox...mamafizz and BumUK both wrote diaries about it on here.