Hi! I had been on mtx for over 12 years. It was doing a great job controling my RA. Several times over the course of treatment my liver enzymes became elevated and had to go off the mtx for several months until the liver enzymes stabilized. During one of the episodes where the enzymes were elevated, I had a liver biopsy which is recommended after long time use because there is the possibility of liver toxicity with mtx. I have been off mtx for a year and a half because I developed a form of TB which may have been related to the long term mtx supression of my immune system. Embrel, Humira and Remicade have also been linked to TB. It is unusual for mtx to be linked with atypical TB, but in my case there did not seem to be any other etiology. Good luck with your treatment!