Lidocaine Infusion for migraine

Has anyone heard of lidocaine infusion NOT working to relieve migraine pain? My 21 yr old daughter, Sarah, hasbeen suffering from migraine pain for 11 years. She just completed a 6 day hospital stay in which she received 180mg/hr lidocaine IV and it did not budge her headache. At one point she had the worst head pain of her life (a new 10 level for her). Her neurologist now says that she doesn't have migraines or at least this episode wasn't a migraine because this treatment is 100% effective in treating migraine and pretty much all kinds of pain. She is very distraught at being discharged with no relief whatsoever. She knew this technique might not help her longterm but had expected at least short term relief and maybe to break this three week long migraine. Any thoughts/experience are welcome.


Bruce (Sarah,s dad)

My daughter had a lidocaine infusion about 6 weeks ago and it worked immediately.  She was admitted this week and the infusion did not work.  The doctor told me that it was impossible that the lidocaine did not work.  She is questioning my daughters pain level.  They decided to repeat the infusion 2 days later and it appears to be working.  My daughter is 20 and has been suffering with these since she was 10.  What other treatments has your daugher tried?