Swelling and pain after half a year of hyaluronic acid chin may be caused by granuloma, infection, folliculitis and other diseases, you should consult a doctor in time to clarify the cause of the disease and then carry out appropriate treatment. 1. Granuloma: If there is persistent swelling and pain after half a year from playing hyaluronic acid, it is possible that the injected material may be in the chin for a long time to stimulate the local soft tissue hyperplasia to form granulomas, which affects the appearance or the swelling and pain for a long time, you should go to the hospital in a timely manner for the appropriate treatment. 2. Infection: after playing hyaluronic acid half a year after the chin swelling and pain may also be secondary to infection, such people will also be accompanied by local redness, skin temperature rise, pain and other symptoms of infection. 3. Folliculitis: there are more hair follicles on the chin, chin swelling and pain after six months of hyaluronic acid may not have anything to do with hyaluronic acid, folliculitis, such people will have a follicle-centered red pimples, localized pain, swelling, can be treated with metronidazole topical under the guidance of a doctor. Hyaluronic acid injection half a year after the swelling and pain may also be related to other diseases, it is recommended to regular hospitals, comply with the recommendations of the specialist physician to improve the relevant examination, after a clear diagnosis, standardized symptomatic treatment.