4 weeks post lip filler the swelling has returned twice after prednisone. It is painful and tingly. What could this be? (photos)

While I cannot provide a formal assessment without seeing you as a patient in my clinic, it appears that you are having a reaction to the product. I suggest stopping the prednisone and having your filler dissolved. I also recommend scheduling this appointment with a board-certified cosmetic dermatologist who is an expert in facial rejuvenation. Once the filler is dissolved and your reaction subsides, this doctor can help you choose the appropriate filler and treatment plan moving forward.

I appreciate your concern. While swelling is completely normal after lip filler injections, the problems you are experiencing sound like they could be related to an inflammatory response rather than the usual post-treatment swelling. I would schedule a follow-up with your doctor once again to determine whether the filler should be dissolved to prevent further issues.

I'm sorry to hear of the issues you are having.  From your description it sounds as if you are having a reaction to the filler.  At this point you may consider having the product dissolved with hyaluronidase.  See an expert injector to discuss this further.