Your Pet’s Health Is Our Top Priority

Learn about the efficacy and safety profile of Seresto®


More than 71 million Seresto® collars have protected dogs and cats globally from fleas and ticks.


We know how important it is to help pets thrive. That purpose drives everything we do every day. It is why Seresto® is designed to help protect pets from fleas and ticks that can negatively impact a pet’s quality of life and may cause dangerous diseases. We provide proven protection against these pests so that you can continue to enjoy special moments with your pets.  

Pet owners rely on Seresto® as a valued and effective vet-recommended solution against fleas and ticks, and we take very seriously the responsibility we have to pet owners. Before it was registered for use, Seresto® was extensively tested by veterinarians and scientists. And it has been thoroughly evaluated by regulators in 80 countries all over the world. That’s why pet owners can be confident in Seresto®. 

Veterinarian putting a Seresto Flea & Tick Collar on a dog

Extensive research and 41 million uses in the U.S. alone by pet owners during the past ten years have demonstrated Seresto®’s safety profile and effectiveness. More than 71 million Seresto® collars have protected dogs and cats globally from fleas and ticks. 

We are committed to helping every pet owner know how flea and tick prevention products can be used properly and effectively. To help ensure that your next collar is a genuine Seresto® product, we recommend customers shop at veterinary clinics or with trusted retail partners whenever possible.  

Learn more about Seresto®, its active ingredients and how the collars work.

See why veterinarian, Dr. Lisa Lippman, recommends the Seresto® collar. 

Here are some answers to commonly asked questions: 


Are Seresto® collars safe?

Elanco's pharmacovigilance team, made up of veterinarians and other experts who study adverse event reports, has not identified a single death caused by the active ingredients in the collar. 

Since Seresto®’s launch in 2012 through 2023, more than 41 million collars have been distributed across the U.S. Over this period, the reporting rate for all incidents related to Seresto® is low and has been trending downward.  

The overall incident reporting rate in 2021 was 17.26 reports per 10,000 collars sold. That’s less than a fifth of 1%. The vast majority of these incidents relate to non-serious effects such as temporary hair loss and mild skin irritation around the application site. 

Pet Poison Helpline, a recognized leader in animal health toxicology and pet health, provided the following statements on Seresto® collars: 

  • “In the medical opinion of our boarded veterinary toxicology experts these collars are a safe and important treatment for the vast majority of cats and dogs.”  
  • “In its totality, we think the science continues to support the safe and effective use of Seresto collars” Pet Poison Helpline, a recognized leader in animal health toxicology and pet health 

We take the safety of our products seriously and thoroughly investigate potential concerns related to their use. Elanco’s team of experts are trained in the science of pharmacovigilance, and they analyze incident reports regarding its products on an ongoing basis, including reviews from outside experts and regulatory authorities. Data are regularly monitored for signals or trends to determine any concerns that need further evaluation. 

 

Are Seresto® collars regulated and tested for safety? 

As a globally marketed product, more than 80 other regulatory authorities around the world have reviewed the safety data collected over the course of Seresto®’s development prior to registration. Many regulatory authorities also require post-approval monitoring and pharmacovigilance reporting.   

The body of regulatory reviews have supported the safety profile of Seresto®. A decade of data tells a specific, strong story of how Seresto®’s benefits far outweigh potential risks. 

The safety and efficacy of Seresto® are continuously monitored and scrutinized by many global regulatory bodies as well as via internal processes. 

 

Have Seresto® collars caused pet deaths? 

There is no established link between death and exposure to the active ingredients contained in Seresto®. 

 

Is there a Seresto® recall? 

There is no evidence in the scientific evaluation conducted for registration or the regularly reviewed pharmacovigilance data to suggest a recall of Seresto® is warranted, nor has one been requested, or even suggested by any regulatory agency. As a result, Elanco continues to stand behind the safety profile of Seresto®. It remains available to consumers as an effective way to protect pets against fleas and ticks that can transmit disease and can impact their quality of life. 

From left to right, a collection of Seresto for Cats, Seresto for Large Dog and Seresto for Small Dog product tins

More commonly asked questions about Seresto®: 

 

How do Seresto® collars for dogs work? 

The Seresto® collar works with a innovative polymer matrix of two active ingredients, which spread from the site of direct contact over the skin surface of your dog: 

  • Imidacloprid has been used in products for years to control flea infestations. 
  • Flumethrin effectively kills and repels ticks. 
  • Flumethrin works together with imidacloprid to provide dual action against fleas and ticks. No other product has this combination of ingredients. 

 

What is sustained release technology?

Seresto® works similarly to a monthly topical in the fact that the active ingredients spread from the site of direct contact over the skin surface. The active ingredients in Seresto® are released from within the collar and, thanks to your pet's skin and coat, spread from head to toes, even the tail. As the active ingredients wear off over time, a new supply is continuously replenished for 8 months. The long-lasting, 8-month duration of Seresto® differentiates it from other flea and tick collars. 

Watch our videos for more information about how Seresto is effective against fleas and ticks

 

Do Seresto® collars for dogs expire? 

There is no expiration date required on the packaging by the EPA for Seresto® for dogs. The product should be kept in its original packaging and stored as directed on the label. 

 

Can I bathe my dog with the Seresto® collar on? 

Seresto® is water-resistant and remains effective following a shampoo treatment, swimming or after exposure to rain or sunlight. Under normal conditions, effectiveness lasts for 8 months. To maintain an 8-month duration, dogs must not be bathed more than once per month. There is no need to remove the collar for bathing. Please use a gentle, soap-free pet shampoo. For dogs that swim once a month or more, the control duration is reduced to 5 months for flea control and reduced to 7 months for tick control.

 

How do I apply the Seresto® collar and take it off my dog? 

How to apply the Seresto® collar on your dog:  

  1. Remove the collar from its packaging.  
  2. Unroll the collar and remove the small plastic connectors from inside the collar, ensuring that no remnants remain.  
  3. Insert the end of the collar through the buckle and loops.  
  4. Adjust the collar around your dog's neck until it fits comfortably on them.  
  5. Two fingers should fit beneath the collar and neck to ensure it's not too tight. Any excess length of the collar beyond an inch past the loops should be cut off, unless it is on a growing puppy, where some additional length may be needed for adjustment as the puppy grows.  
  6. Check periodically and adjust fit if necessary, especially on growing puppies. 

Watch our application video for more information.  

How to take the Seresto® collar off your dog:  
Squeeze the outer sides of the buckle while pulling from the other end or side of the collar. Some may find it just as easy to cut the collar off before applying the new Seresto® collar. 

 

Do Seresto® collars for cats expire? 

There is no expiration date required on the packaging by the EPA for Seresto® for cats. The product should be kept in its original packaging and stored as directed on the label. 

 

How do I apply the Seresto® collar and take it off my cat? 

How to apply the Seresto® collar on your cat:

  1. Remove the collar from its packaging.  
  2. Unroll the collar and remove the small plastic connectors from inside the collar, ensuring that no remnants remain.  
  3. Insert the end of the collar through the buckle and loops.  
  4. Adjust the collar around your cat's neck until it fits comfortably on them.  
  5. Two fingers should fit beneath the collar and neck to ensure it is not too tight. Any excess length of the collar beyond an inch past the loops should be cut off unless it is on a growing kitten, where some additional length may be needed for adjustment as the kitten grows. Also, make sure the collar cannot be pulled over the head.  
  6. Check periodically and adjust fit if necessary, especially if you have a kitten that is rapidly growing.

Watch our application video for more information.  

How to take the Seresto® collar off your cat:
Squeeze the outer sides of the buckle while pulling from the other end or side of the collar. Some may find it just as easy to cut the collar off before applying the new Seresto® collar. 

 

Why can Seresto® be used on dogs and cats? 

Seresto® kills fleas and ticks.  

Seresto® was designed with specific ingredients at doses that are active against fleas and ticks. Studies show that fleas and ticks are highly susceptible to the combination of imidacloprid and flumethrin found in Seresto®.  

The Seresto® collar works with a unique polymer matrix of two active ingredients, which spread from the site of direct contact over the skin surface of your dog and cat. The active ingredients in Seresto® are released from within the collar.  

As the active ingredients wear off over time, a new supply is continuously replenished. Imidacloprid has been used in products for years to control flea infestations. Flumethrin effectively kills and repels ticks. 

 

How do I know if the Seresto® collar I purchased is authentic? 

It’s crucial that pet owners purchase real and genuine Seresto® products from authorized veterinary clinics and trusted retailers to help ensure product authenticity and performance. Find Seresto® at a clinic or retailer online or near you

 

Where can I find more details about Seresto® and complete application information? 

Click on the product below to learn more:  
Small Dog
Large Dog
Cat