Hi everyone, just found this board, find it very interesting. I have Psa and started mtx December, had to stop for two weeks as I got mouth ulcers then when I was due to start again had sinus infection and heavy cough so four weeks later I restarted them 10mgs weekly with folic acid six days a week. I am having terrible headaches most days, some are so bad I just have to lye down In a Dark room, will persevere with them as have already tried sulphasalzine unsuccessfully. Not back in clinic till march so hope they settle before then.