Can't advise. Can't advise you to medicate yourself. The tooth needs to be treated by a dentist anyway, and the antibiotics won't fix the problem, just mask the symptoms. Call a local dentist who will prescribe what is best for your situation. The abscess will only get worse without care.
See a dentist. An antibiotic therapy for dental abscess is indicated only when drainage cannot be achieved or the patient shows signs of systemic involvement. Penicillin is the most useful antibiotic for dental infection and prescribed for 7-10 days.. Remember, the only way to cure a dental abscess is with dental treatment.
Dental Abscess. I agree that first of all you should see a dentist. That said, neither of these antibiotics would be a first choice for treatment. Erythromycin frequently causes nausea and vomiting, and is a relatively weak antibiotic. Clindamycin is a a very strong antibiotic, but would generally be used in patients allergic to penicillin or with a serious infection. Any antibiotic can have serious side effects.