This research is studying a drug called cefoxitin already approved by the Food and Drug Administration (FDA) to reduce the risk of infection after surgery to remove an appendix. Researchers are studying a large group of people to continue to learn how best to dose antibiotics. This research will compare the current standard treatment which is a single dose prior to surgery to a new method that includes adding another dose of cefoxitin within 30 minutes of starting the surgery. This study will measure cefoxitin concentrations in blood, fat, and appendix tissue samples to compare the standard dosing method to our new method. This information will help us figure out the right dose of this drug to prevent infection after surgery to remove an appendix.