text: Yes, it may cover most of the bacteria that typically cause oral abcesses.  However, it does not cover what we call "anaerobic organisms".  If you do not feel better after 24-48 hours, or if it gets worse in the next 24 hours, talk to your doctor to get an alternative (clindamycin or augmentin).  Also, septra has a sulfa component, so please do not take it if you have had a severe allergic reaction to sulfa in the past.