One session lasts twelve to twenty-four months, varying by product. It fills immediately and settles over four weeks, which is how long the surrounding tissue takes to adapt to the new volume. A large amount goes into a deep layer here, so it lasts longer than at other sites.

Downtime of five to ten days is needed. A large volume across a wide area means the tissue takes longer to adapt, so swelling can last more than a week. Cutting down on long periods of sitting for a few days keeps pressure from distorting the shape.

Because a large volume goes into a wide area, the product type and total amount should be confirmed in advance. Unlike facial filler this can run to hundreds of millilitres, which changes the cost and the burden considerably. Some product lines use materials other than hyaluronic acid, so check with the clinic.