Hi I'm on 150mcgs of Levo for hashimotos . I haven't had my levels checked in some months but I am concerned as I have had 2 severe sinus infections since September . I got rid of the first after about 7 weeks & now another has started since Christmas Day. It's making me feel terrible & doctors seem to have no sympathy & give me sudafed which doesn't do anything . What can I do to help myself & build a stronger immune system? I've been plagued my whole life with respiratory infections but when I started Levothyroxine they went away - for 14 months . And suddenly they are back with a vengeance ! Help!