BY: SAMANTHA BARTLETT, DVM
The Seresto collar is a flea and tick collar containing two active ingredients: imidacloprid and flumethrin. The collar is sold by Elanco Animal Health. Since it is a topical product with no systemic mode of action, the collar is regulated by the Environmental Protection Agency (EPA). Seresto was approved by the EPA on the basis of more than 80 studies focusing on safety, toxicity and efficacy.
The collars came into the spotlight in May 2021 after a report from USA Today and the Midwest Center for Investigative Reporting found that the EPA had received more than 75,000 incident reports since the Seresto collar was first introduced on the market in 2012. The collars are alleged to be responsible for 2500 pet deaths and more than 98,000 incidents of harm to humans. During that time frame, Elanco claims to have sold more than 33 million collars. On July 15, 2022, the Subcommittee on Economic and Consumer Policy, which belongs to the U.S. House of Representative’s Committee on Oversight and Reform, held a hearing on Seresto collars.
The subcommittee released a report that requested a voluntary recall of the collars. The report also requested that the EPA cancel Seresto’s registration and improve animal safety studies and the collection of pet incident data. The EPA is currently conducting a review of the collar and incident frequency and severity.
In a written statement to the congressional subcommittee, Jeffrey Simmons, President and CEO of Elanco Animal Health, defended the Seresto flea and tick collar as safe and effective. He noted that adverse incident reports do not necessary mean that the incident was caused by the product. According to Mr. Simmons, Elanco’s pharmacovigilance team is not aware of any deaths caused by the active ingredients of the collar.
Support has also come from the AVMA and the Pet Poison Hotline. Gail Golab, AVMA chief veterinary officer, added that while the risk of adverse events is present, the risk of health conditions and disease caused by parasites is much greater. In May 2021, veterinary toxicologists from the Pet Poison Hotline deemed that the benefits of the Seresto collar outweighed the “extremely rare risk of a serious adverse event.” The Pet Poison Hotline has handled about 400 cases involving the collar – most of which involved ingestion of the collar by dogs – and the adverse events were mild.
The AVMA has requested that the EPA not cancel Seresto’s registration until a full evaluation of the data has been conducted. They are hopeful that once all of the data has been reviewed, a clearer picture of the collar’s safety will come to light and the collar will be able to stay on the market as a safe, accessible option for flea and tick prevention.
