Under-eye filler has earned a curious reputation for being both a top shot in injectors’ offices and, we’re told, the most problematic of procedures. In recent months, several practitioners have taken to social media, cautioning against using certain fillers in the delicate tear trough area and highlighting how smart placement, technique, and patient selection can help stave off complications, both in the short-term and down the line. (Tear trough filler, we should note, is an off-label treatment, as no injectable gel is currently approved for the area.)

“The under-eye region is complex and one of the more difficult places to treat on the face, for finessed results,” says Dr. Amelia K. Hausauer, a board-certified dermatologist in Campbell, California. Various factors contribute to the trickiness of the tear troughs, including the quality and substantiveness of the tissues under the eyes. Not only is the skin the thinnest on the body, but fat is also in short supply here; taken together, these make the area highly unforgiving. “There’s less tissue to cover the filler, so bumps, swelling, and a blue discoloration from gel placed too high in the skin, termed the Tyndall effect, are more common,” Dr. Hausauer explains. Moreover, whatever fat does exist in the region tends to droop and bulge, forming bags, which are challenging to camouflage with filler, especially if your skin lacks snap.