Last November I started getting sick with a sinus headache and fever. At the end of a week, I was so sick that I ended up throwing up in a bathroom stall at work. The doctor diagnosed a sinus infection. Not unusual for someone with allergies, but I hadn't had one in years. I got a prescription for antibiotics, and thought that was the end of it.

Nope. For a few days after I started the antibiotic, my fever abated and I felt better. But even before I finished the last dose, I was feeling...