How many liters do I need for hyaluronic acid butt injections?

Hello,It is Dr.Hong from Fresh PS Clinic, S.Korea Seoul.To address your inquiry, for full forehead volume enhancement, typically 5cc to 7cc of filler is required. For the buttocks, around 10cc to 20cc per side may be needed.
However, as a surgeon specializing in body and face contouring, I want to emphasize that I am not an advocate for large-scale body fillers. While small quantities of filler can be used safely for the face, I strongly advise against using large amounts for the breast or buttocks. There are safer, more body-friendly alternatives available—such as the non-surgical Brazilian Butt Lift (BBL) using fat grafting.
Fat grafting offers a lower risk of allergic reactions or inflammation compared to fillers, and it has the advantage of being a natural, long-lasting solution. Moreover, there's no limit to how much fat can be injected, and additional treatments can be performed over time if needed.
I hope this helps clarify your concerns.
Best regards,Dr. Hong