Thank you for your question elizagriffiths. Fillers are used to restore lost volume in and enhance the appearance of the face. I am unclear of your questions.The first question is whether dissolving lip fillers will get rid of an infection. The answer is that it depends on the infection. If it is a flu-like illness, cold, etc., then dissolving the filler will not affect the infection. In the case of a cold sore, treatment is with antivirals such as valacyclovir, not dissolving the filler. If the filler leads to a granuloma with biofilm, then dissolving the filler along with taking the antibiotics usually leads to resolution of the infection.The second question is whether fillers can be placed in the lip after previous placement of fillers in the lip and dissolution of the filler. Having a previous filler dissolved is not a contraindication to having more filler placed in the same area. But it is important to know why the filler was dissolved. For example, if the desired effects were not achieved then a different approach may be taken. For example if more fullness is desired in one area, that area can receive more product.A number of fillers are available for the lips. Those indicated are hyaluronic acid products such as the Juvederm family of fillers, the Restylane family of fillers, and Belotero. I do not recommend non-hyaluronic acid products such as Radiesse, Sculptra, or Bellafill. My new favorite products for lip enhancement are Vollure to provide volume and Volbella for subtle enhancement and definition. These use Vycross technology which allows for a longer duration of action. Please consult with a doctor for specific recommendations. Good luck!