Pain meds. In addition to the antibiotics mentioned previously, i would also recommend otc non-steroidal anti-inflammatory medications like advil, (ibuprofen) if you can take that to help supplementally reduce the pain until the antibiotic takes full effect. If the pain continues, you wil want to see your treating dentist again.
Antibiotic, pain med. Antibiotic is necessary when there is an infection in the tooth and bone at the root tip area. Sometimes the bacteria that causes the infection can be resistant to the antibiotic prescribed, so another one is necessary. The pain usually subsides when the infection is under control. It can take up to 4-5 days. In the mean time pain med will help.
Medication. Antibiotics, narcotic pain medication. Sometimes treatment ineffective. Keep dentist informed.