Drugs.com states that Restylane, a product that is injected into facial skin to add volume and fullness, can cause swelling, redness, bruising, or tenderness following treatment. These side effects are typically mild and can last from 7 to 14 days.
The manufacturer's website states that Restylane is an FDA-approved dermal filler that is injected into facial wrinkles and folds to smooth lines, and it is used in lips to add fullness. It is made of hyaluronic acid, a sugar naturally found in the body. The results are not permanent and can last from 6 to 12 months. Wikipedia states that the effects of Restylane can be easily reversed by treatment with hyaluronidase, an enzyme that increases the natural degradation of hyaluronic acid.