I've been using Imuran 150mg daily for the last five years. Every 3 month I do blood work to keep a watch on my liver. My ALT value (liver inflamation) has alway been between 12 and 18, at the lower end for the last year. Thursdays test came back at 45 up from 12 in Nov 2007, I'm a little panicked until I can talk to my G.I. Acceptable levels is below 36. I'm hoping this is just a lab error.