I have an abcess in a root treated tooth, how long for the swelling from an oral abcess to go down once antibiotics are being taken ?

Begin in 24 hrs: Antibiotic prescribed to a fluctuant infection or abscess should start to take effect after 24 hours, at which the swelling should start to reduce. The drug of choice for a root canal tooth is clindamycin, unless the patient is allergic to the medication.

New or Old RootCanal: If recent root canal therapy - usually about 1-2 weeks. If it is an old root canal, then it will not go away unless the dentist retreats the root canal tooth by re doing the root canal therapy or doing a surgical clean out at the end of the root (apicoectomy).

24-48 hrs: Antibiotics take 24-48 hrs. To get to the source and start to decrease the swelling. When a root canal is performed on a tooth that has accompanying swelling , it is often adventageous to incise and drain in addition to antibiotic therapy. This sometimes mitigates the need for peri- apical surgery later. About 10% of root canal treated teeth that have swelling need either an i and d or periapic.