Pain killer you may get over the counter if you mention teeth pain but that is temporary relief. You may get your teeth checked at dental clinic

Hello There might be chances that the RC treated tooth must have infection again. Kindly consult with your nearest dentist for xray

Hello The pain in the already root canal treated tooth might be a sign of secondary infection. Please visit the dentist to get an x-ray and confirm and go for the treatment according accordingly.

Hello, Severe pain on biting in a tooth that had RCT 5 years ago may indicate re-infection, root fracture, or periapical inflammation. Painkillers can give temporary relief, but antibiotics are not needed unless there is swelling or fever. Please upload a recent X-ray (IOPA/OPG) of the affected tooth so I can guide you more accurately. Meanwhile, avoid chewing on that side and consult a dentist soon.

Pain on biting after a root canal can occur due to reasons like infection around the root, high bite, crack in the tooth, or inflammation of supporting tissues. It is important to examine the tooth clinically and take an X-ray to identify the exact cause before prescribing treatment. Please avoid chewing from that side until evaluation.