I have a sinus infection that is pretty bad, the doctors have me on Biaxin (Clarithromycin), but ever since I started taking the medication I've got this really painful lump inside my throat, it doesn't hinder my breathing or anything but it's making me gag everytime I swallow and causing me to throw up a lot. Does anyone know what is causing it? I ruled out it being a tonsil stone or phlegm, and it's got me really worried.