Hi. Mixing different brands of hyaluronic acid fillers is absolutely fine. No two clinicians have the same ethos with regards to lip fillers so make sure that the new clinician knows exactly what you want.
There is no issue in combining or layering different hyaluronic acid-based fillers either at the same visit or weeks later. Most importantly, get your treatment by an expert such as a dermatologist to optimize results and minimize any risks.
Thank you for your question. Yes, Juvederm can be safely used after emervel to further augment your top lip.
Yes, they can. Both are HA cross linked fillers, so I have no problems overlapping Juvederm and Emervel.
All the best
Dr Davin Lim
Laser Dermatology and aesthetics