Hyaluronic acid fillers are a safe and effective aesthetic medicine modality, but some patients experience significant pain and bruising from dermal filler injections. Adding lidocaine may help with pain, and many clinicians also will add epinephrine to filler injections, believing they’ll achieve even less pain and mitigate bruising because of epinephrine’s vasoconstrictive effects.

However, quality evidence is lacking to support the addition of epinephrine, according to Dr. Amir Moradi, a facial plastic and reconstructive surgeon in private practice in San Diego. He conducted a split-face study that found no benefit from adding epinephrine to hyaluronic acid injections, and presented his results at the Summit in Aesthetic Medicine in Dana Point, Calif.

The study enrolled 30 patients in a double-blind, split-face comparison study of the hyaluronic acid filler Belotero (BEL) alone to Belotero with lidocaine (BEL-L), and to Belotero with lidocaine and epinephrine (BEL-LE). Patients received superficial to mid-dermal injections for perioral lines, and investigators obtained pretreatment photos and assessed wrinkle severity on the 5-point Merz scale.

Patients were allocated randomly and equally to treatment arms, so that 10 received BEL and BEL-L, 10 received BEL and BEL-LE, and 10 received BEL-L and BEL-LE. Each patient received a maximum of 1 mL of filler on each side of the face. An assistant prepared syringes in a manner that made them indistinguishable, so the operator and patient were blinded to treatment arm. All patients received massage and ice to the perioral area immediately after treatment.

Investigators asked patients to report the pain they experienced during injections on a 10-point Likert scale immediately after their injections were complete. Bruising was assessed by the physician investigator, by another blinded evaluator, and by the patients themselves pretreatment, and on days 1, 7, and 14 after injections. Because no validated standardized bruising scale exists, the investigators devised a scale of 0-3 to describe mild, moderate, and severe bruising according to the visibility and size of the discolored areas.

Contrary to anecdotal reports and against the investigators’ expectations, patients saw no significant difference in either pain or bruising with the addition of lidocaine, with or without epinephrine, to the hyaluronic acid dermal filler. Patients in all treatment arms generally had the worst bruising at day 1, with a resolution by about half at day 7, and bruising gone or nearly gone by day 14.

Calling for more and larger studies in this field, Dr. Moradi noted that the “limited benefit of lidocaine could be due to not waiting long enough for lidocaine to fully take effect.”

For pain, Dr. Moradi said in an interview, “How and when you ask the question really makes a difference. Because if you wait even 30 seconds afterward, it can change the answer.” He noted that his results showed no improvement in pain with lidocaine compared with hyaluronic acid alone. He plans further investigation using an assessment method that will allow patients to report pain during injections.

Planning more study into whether lidocaine, alone or with epinephrine, helps pain and bruising, Dr. Moradi expects to see some benefit for the adjuncts when a physician needs to go back and reinject an area. However, the field needs more well-designed studies with standardized assessments, he said. “We need to look at what the evidence says,”

Dr. Moradi reports that he has financial disclosures related to Allergan, Galderma, and Merz.

On Twitter @karioakes