Would starting a course of macrobid cause achiness (neck and shoulder muscles as well as jaw pain) and a severe frontal area headache? It feels a bit like a flu like feeling. First time I ve taken it, I normally take cipro and it really never bothered me. I m only on day 3, and symptoms did not start until late yesterday. The HA has subsided to just minor with ibuprofen but it did take nearly 12 hours.