sinusitis
"Been taking this for five days.  The pressure in my sinus is lessening, and my fever is gone, but mucus production has increased, and so now my cough is worse.  Does this mean it's not working?  
The best way I've found to avoid the adverse digestive effects (vomiting, etc) is to take a strong probiotic to replenish what the antibiotic kills.  You can ask your doctor for a prescription strength probiotic (they prescribe them for patients with ulcerative colitis) or find them in pill or drink form at a health food store.  "