Has anyone who is taking Leflunomide had any problems with underarm/top of breast pain? I am taking Leflunomide 10mg and this is my fourth week on the drug this time. I have taken it previously for 6 months but had to come off it then along with Arcoxia as my tongue had gone numb but I also did notice that I had this pain then and once off it the pain went away. Am trying it again as I am running out of options and possibly the numb tongue was the Arcoxia and not the Leflunomide so hence trying again. Any advice please would be very welcome.