How long do fillers for hollowness under the eyes last?

Thank you for your question,
The fillers that I typically choose to use in this area of the face usually last 1-2 years depending on the filler of choice. I think it is important to state that patients who have bags under their eyes typically are not good candidates for this procedure, because usually the bags can be accentuated leading to a unpleasant result. Fillers can be used to lift cheeks and have a great satisfaction rating. I usually like to use Voluma for cheek lifting. Voluma can last up to 2 years. For under the eyes, I will either choose Volbella for mild hollowness or Vollure for moderate cases. For severe I may perform a combination of the 2 at separate appointments. I think a picture of you would help us give you better advice.  

Hyaluronic acid fillers that are thin work well under the eyes when properly injected. I like Vollure made into microdots and injected deeply with a 31 gauge needle. Vollure is said to last up to 1 1/2 years. I have never seen a HA filler last anywhere close to 6 years. Best Wishes, Maurice Vick MD

Typically under eye fillers last between 1-2 years. 6 years seems a little far-fetched. When injecting the tear troughs some patients also gain a bit of volume in the cheeks. Helping to correct the under eye area and also lift the cheek. Best of luck