I'm actually currently on Bactrim for an infection. Not for Lap Band surgery (that was almost 8 months ago), but for an emergency strangulated hernia surgery.
I had redness around the drain coming out of my stomach so I went in to have it removed early the Sunday before last. They removed it but it remained very red and a little sore. Imagine my shock when a week later, on Saturday, the hospital calls me and says "You need to contact your doctor, your wound culture came back positive for a Staph infection".
I panicked momentarily because I know Staph can be really nasty. When my doctor's office called he told me there's different types of Staph, that the kind I had wasn't horrible, and he was calling me in a prescription.
I have been on the antibiotic for 6 days now. All the redness and soreness is completely gone and it's healing nicely.
Good luck, I'm sure yours will clear right up too!