What antibiotics can treat pelvic inflammatory disease effectively?

PID: This depends upon the cause of the pid. At the outset this is often caused by a single organism, like chlamydia or gonorrhea, but as time goes on it may become polymicrobial (many different bacteria). If you go onto the cdc website and look for std treatment guidelines this may be very helpful. Good luck.

It depends: This depends on the suspected pathogen causing the infection -- and you need a medical evaluation for effective treatment. Some useful antibiotics include cefoxitin, doxycycline, clindamycin, gentamycin, etc. Other agents may be needed in addition, or instead.