I completed 2 rounds of Zithromax (sp?) approximately 2 weeks ago due to a sinus infection. I had a pretty considerable amount of couging with the infection, and the cough itself took around a week to really improve. Just within the last week or so, I have noticed a strange feeling in my back. Sometimes it is a dull ache, sometimes just a full feeling. It occurs right over or slightly under my shoulder blades, mostly on the left side. Is it a possibility that the coughing caused some kind of muscle injury? How long should it take for something minor like that to remedy itself? I'm a total hypochondriac, so this has me worried enough that I am considering asking the doc for blookwork, despite having few other things to worry about (occasional joint pain in elbows, tense/sore feeling around the collarbone). As far as I can tell I don't have any swollen glands, my appetite is good, and I don't think I've had a fever since the infection cleared up. Any input anyone has would be appreciated!