Risk of severe adverse reactions to an injectable filler based on a fixed combination of hydroxyethylmethacrylate and ethylmethacrylate with hyaluronic acid.

Background: Hydroxyethylmethacrylate and ethylmethacrylate in a fixed combination with hyaluronic acid has been used as an injectable filler for nearly a decade. Severe adverse reactions have been associated with this filler.

Objective: To characterize the adverse reactions to this filler.

Methods: Data from the Berlin registry for adverse reactions to injectable fillers were analyzed. The registry is a partially population-based registry with the aim of collecting adverse reactions to injectable fillers. Patients were interviewed based on a standardized questionnaire.

Results: Thirty-four of 118 (28.8%) registered patients were treated with this filler. Of 95 treated areas, 87 responded with a reaction (91.6%). The most frequently observed adverse events were the development of nodules (n=85) in 87 affected areas, discoloration (n=39), erythema or inflammation (n=32), and swelling (n=24). Most nodular reactions were rated as severe. The mean time after the last treatment until appearance of an adverse reaction was 23.1+/-22.8 months.

Conclusions: Adverse reactions to this methacrylate filler are common. The mean latency period for these mostly severe rated reactions was nearly 2 years. Based on the frequency and severity of these reactions, the use of this filler does not seem to be advisable.