I have read that zantac may cause a false positive for meth, but I am not sure how true it is.
My Goodness you are on a lot of Drugs. ? Is your only complaint dirty test results.? I can only speak for myself, I also have Primary Progressive MS. I was DX 23 years ago. I can only guess but it seems that most of these medications would make you feel pretty zonked by themselves, but taken in combination I know I wouldn't be thinking very clearly. It might be a good idea to have you and your Medications reevaluated by your PCP ....
ShadowsSisier
PS: I am also treated by a Pain Management Doctor, and I am Only on Morphine and Zanaflex....I am so grateful that he is very conservative in his treatments.