From feedback from my own patients, I don’t believe it’s painful to have tear trough filler. It just feels a little odd because it’s so close to the eye. Sensation may also be different depi get whether the practitioner uses a needle or cannula. A cannula is a long, blunt tipped needle, and the entry point is often more toward the mid pupillary line in the cheek. Because of the blunt tip, it can kind of feel like a popping sensation. A needle may also be used, but no popping or tugging sensation, as the needle is sharp and goes through all the layers of the skin, muscle and fat pad.
Numbing the area will depend on the treating practitioner. Personally, I do not numb the area. If the practitioner is using a cannula, they “may” put a bleb of local anesthetic, but I do not, as it is one small incision with a needle.