Hello, Doctor. I was diagnosed with GCA (arteritis) having terrible headache, like knives or needles, in 2011. Since then I take prednisone, decreased now at 3mg/d. For about 2 month I have a very dry mouth that I weak up during the night 2-3 times completely dry. I think I have Sjogren s syndrom now. Is this a side effect of the prednisone? Is it good if I will improve my immune system? Steriana