Nuerologist states it is one of the BEST medications for the pain I am having

I take several (at least 13) medications. My Neurologist said that the ones I was on would NOT interfere with the Ultram ER....well, according to my Pharmacist, if I mix it with the Flexeril or Doxepin that I am on, it WILL cause 'delayed' seizures. I already have a lot of health issues, and the Doxepin has been given to me to relieve continual stinging/irritation/pain had. I do NOT want to add seizures to things, so I was told that if I were to STOP taking one of the two medications I should be alright with it, however I was told that the best one (which does the most for me) for me to get off of if possible is the Doxepin. Can anyone tell me that IF I get off of the Doxepin and have another Muscle Relaxer (Zanaflex), if I would STILL be at some type of risk of seizures with taking the Ultram ER. I want disparately to be out of the "hell" I have been in, but I don't want to ADD anything bad either. Thanks much.......J.