How should i treat a swollen lip?

It depends: Depending on the cause, the treatment varies. If the swelling is due to a dental infection, you will need to see a dentist. If it is due to an allergic reaction, your physician is the one to call.

See a PCP: Lip swelling may be related to a local (e.g. trauma) or and it can be the earliest sign of a systemic disease. See your doctor for evaluation, tests and treatment.