It is extremely rare that unexpected swelling occurs by injecting hyaluronic acid. In that case there is a possibility of allergic reaction (which is said to be very difficult in theory).
In some cases it may be necessary to inject an enzyme agent that degrades hyaluronic acid.
More commonly seen are “lumps” and “bruises”, but the lump is more common when hard filler is used or the skin is thin at the injection site.
Regarding bruises, if you are taking medications or supplements that have blood-thinning action (Vitamin E, fish oil, aspirin, etc.), those who came to treatment after stopping them for more than one week It is safe.
If that is not the case, We think that big bruises will not happen often.
For more details, please visit this page. Thank you.