While on Remicade, Cimzia and Humira, I got frequent upper respiratory infections. Haven't been bad the last 9 months or so, though, because I've been on prednisone and maybe that is helping keep it away. It's a chance you take when on medicines that weaken your immune system. Only you and your doctor can decide if it's worth taking you off of Remicade for, but any of the biologics and many of the other meds can have the same effect.
Crohn's Disease, Acid Reflux/Gastritis, Hashimoto's Thyroiditis, Endometriosis, Arthritis, Depression/Anxiety. Too many meds to list them all. =)