Had a root canal on #12 which also has a periodical abscess. i'm on day 2 of antibiotics. the abscess has doubled in size and i feel like i have a sinus infection. will this go eventually go down?

Go back to dentist: If you have an abscess it may need drainage. Antibiotics will only help to prevent its extension to other areas and not cure it without surgical intervention.

Periodontal Abcess: Call the dds who performed the root canal immediately so that he can examine you. If you also have a periodontal abcess, you may have a combined perio-endo lesion, which can exaggerate the symptoms usually seen with any abcess. The end of the root of tooth #12 is near the sinus above the roots of the teeth, which may make it feel like you have a sinus infection. Continue to take the antibiotics.

Possibly: But if has doubled in size it might have to be drained.. Call your treating dentist immediately to let them know things are not getting better after 2 days.

With proper treatmen: This is an acute flareup of the periapical lesion. It happens occasionally in teeth with periapical lesions. Antibiotics and an incision and drainage is the proper treatment.

Yes it will: Yes. It usually takes 3-5 days for you to notice any reduction in the swelling while taking antibiotics. The swelling is the bodies way of reacting to the increased bacterial activity in the area and the body is trying to contain the problem. Once the swelling is gone, then the periodontal abscess needs to be addressed to remove the irritants that caused the abscess.