Seresto Flea Collar For Cats


Flea collars are an effective way to help protect cats from flea and tick infestations. Collars are worn around the neck and provide continuous pest control by slowly releasing active ingredients onto the skin and coat. This creates a barrier that repels and kills fleas and ticks before they can bite and cause problems.

Seresto is a popular flea and tick collar that provides up to 8 months of continuous protection. It uses innovative technology to slowly release the active ingredients imidacloprid and flumethrin over time. Seresto collars have been shown to be safe and effective when used as directed.

In this article, we’ll take a closer look at how Seresto flea collars work and their benefits for cats. We’ll also cover potential side effects, precautions, cost, and comparisons to other flea collar options.

What is Seresto?

Seresto is a flea and tick collar for cats and dogs that provides continuous protection against fleas and ticks for 8 months. It was developed by Bayer and is now manufactured and sold by Elanco Animal Health (

Seresto contains two active ingredients – imidacloprid and flumethrin – that work together to repel and kill fleas and ticks. Imidacloprid attacks the nervous system of fleas and ticks, while flumethrin repels and kills ticks. These ingredients are gradually released from the collar in low concentrations and spread across the animal’s haircoat.

One of the key benefits of Seresto is its long-lasting 8 month protection. Other flea and tick collars may only protect for 3-5 months. The slow-release technology allows the ingredients to remain effective over 8 continuous months without needing to be reapplied.

Seresto comes in different sizes for cats and dogs. It is designed to be water-resistant and can be worn while swimming or bathing.

How Does Seresto Work?

Seresto contains two active ingredients, imidacloprid and flumethrin, that work together to kill and repel fleas and ticks on cats and dogs. Imidacloprid attacks the nervous system of fleas and ticks, causing paralysis and death (1). It is effective against larval, nymphal, and adult stages of fleas. Flumethrin works by repelling fleas and ticks and also disrupts their nervous systems. Flumethrin is toxic for ticks and interrupts the flea life cycle by preventing egg hatching and larval development (1).

When the Seresto collar is applied to a cat or dog, the active ingredients are slowly and continuously released from the collar in low concentrations and spread over the animal’s hair coat through contact. This provides long-lasting flea and tick control for up to 8 months. The active ingredients bind to receptors in the skin and hair and remain effective even after getting wet. They are also insect growth regulators – stopping the flea life cycle and preventing infestations (2).

Seresto starts killing fleas on cats within 24 hours of application. It is effective against flea larvae within two hours of contact and newly emerged adult fleas are killed within two hours after jumping on the cat (2). This means Seresto kills fleas rapidly before they can lay eggs and cause an infestation.

Benefits of Using Seresto

The Seresto flea and tick collar provides long-lasting, convenient protection against fleas and ticks for cats. Some key benefits include:

  • Kills and repels fleas and ticks – The active ingredients in Seresto, imidacloprid and flumethrin, work together to repel and kill fleas and ticks.
  • Long-lasting – Seresto collars provide continuous protection against fleas and ticks for 8 months. Owners only need to apply the collar once per season for effective prevention.[1]
  • Water-resistant – The Seresto collar maintains effectiveness even after getting wet, making it ideal for cats who love playing in water.[2]
  • Non-greasy – The collar continuously releases the active ingredients from its polymer matrix onto the cat’s fur in low concentrations without leaving a greasy residue.

By repelling and killing fleas and ticks for up to 8 months, Seresto can greatly reduce the risk of flea infestations and diseases transmitted by ticks. The long-lasting, water-resistant, and non-greasy collar provides a convenient option for protecting cats against these common parasites.

Potential Side Effects

While Seresto collars are generally safe when used as directed, some cats may experience side effects from the active ingredients imidacloprid and flumethrin. Common side effects include:

  • Skin irritation – Some cats may develop redness, itching, or rashes where the collar sits on their neck. This is likely an allergic reaction to the ingredients. According to, skin irritation is one of the most frequently reported side effects.
  • Hair loss at application site – The ingredients in Seresto can cause localized alopecia (hair loss) around the collar area. Cats may lose hair where the collar sits on their neck.
  • Hypersalivation – Some cats may drool excessively after a Seresto collar is applied. According to, this is not a serious side effect but owners should monitor their cat.

In most cases, these side effects are mild and temporary. However, it’s important to closely monitor your cat after applying a Seresto collar. Remove the collar if side effects are severe or persistent.

Precautions When Using Seresto

There are some important precautions to take when using the Seresto flea collar on cats:

According to the EPA, avoid direct contact with the collar as it contains pesticides that can be absorbed through the skin. Supervise children and pets when they are around a cat wearing a Seresto collar. Wash your hands thoroughly after handling the collar.

Monitor your cat’s behavior closely after first applying the Seresto collar. Some cats may experience skin irritation or neurological reactions like lethargy or seizures, although these side effects are rare. Remove the collar if any abnormal behavior develops and contact your veterinarian.

Do not combine Seresto with other flea and tick control products according to the manufacturer’s label. Using multiple pesticides simultaneously increases the risk of overexposure.

Take care to cut off any excess collar length to prevent your cat from chewing on the collar. Consult your veterinarian if you have any other concerns about safely using Seresto for your cat.

Cost and Availability

Seresto flea collars for cats typically cost between $40 and $60. The exact price can vary depending on the retailer, sales promotions, and collar size (for cats under 10 pounds or over 10 pounds). Some common places to purchase Seresto cat flea collars include:

  • Petco – Prices range from $48 to $58 depending on collar size. Can be purchased online at or in-store.
  • Amazon – Often available for around $50 with free shipping for Prime members. Find listings at
  • Walmart – Usually priced from $47 to $57 based on collar size. Check availability on

Third party online retailers may offer Seresto collars at discounted prices compared to major pet stores. Always be sure to purchase from a reputable seller. Beware of counterfeit products being sold at very low prices.

Application and Maintenance

Putting on and maintaining your cat’s Seresto collar properly is important to get the full 8-month protection. Here are some tips:

  • Make sure to remove any old flea collars before putting on the Seresto. Only one collar should be worn at a time.
  • The collar has a locking mechanism. To put it on, unroll it and wrap it around your cat’s neck, then insert the end into the lock. Listen for a “click” sound to ensure it’s secured.
  • Position the collar at the base of your cat’s neck, close to the shoulders. It should fit snugly but still allow two fingers to fit between the collar and neck.
  • Check the fit regularly, especially in growing kittens. Loosen if needed to maintain that two finger space.
  • Do not cut or trim the collar – this can impact effectiveness.
  • Replace the collar after 8 months of continuous use. Mark your calendar to remember when it’s time.
  • Remove the collar before applying any topical treatments like flea/tick spot treatments.
  • If the collar becomes damaged or lost, replace it immediately to maintain protection.

Following these application and maintenance instructions will keep your cat protected from fleas and ticks for a full 8 months with each Seresto collar.

Seresto Compared to Other Flea Collars

Seresto flea and tick collars have some key advantages compared to other major flea collar brands like Hartz Ultraguard and Adams Plus Flea & Tick Collar for Dogs and Cats.

One of the main differences is the length of protection provided. According to The Spruce Pets, Seresto collars provide 8 months of continuous flea and tick protection, while most other flea collars only protect for 3-5 months. The longer protection period means fewer applications per year are needed with Seresto.

Additionally, Seresto uses a slow-release technology that emits active ingredients from the collar gradually over time. This provides more consistent and reliable protection compared to flea collars that rely on topical contact alone. As noted by Sobaken Pets, Seresto’s slow-release system makes it more effective than many competitors.

When it comes to safety, Seresto collars have undergone extensive testing and are EPA approved. Other flea collar brands may use harsher chemicals or have more reports of skin irritation in pets. Seresto aims to balance efficacy with skin tolerance, according to veterinarians.

One potential downside is that Seresto collars tend to be more expensive than generic brands. However, given the longer protection and advanced technology, most experts say the extra cost is justified by the performance and reliability.


Seresto is a flea and tick collar that provides long-lasting protection for cats. The active ingredients in Seresto, imidacloprid and flumethrin, work together to repel and kill fleas, ticks, and lice on cats for up to 8 months. Key benefits of using Seresto on cats include convenience, no mess, and continuous protection without monthly applications. While side effects are rare, some pets may experience skin irritation. Overall, Seresto collars are veterinarian-recommended and offer a safe, effective way to control fleas and ticks on cats when used as directed.

Based on customer reviews and efficacy studies, Seresto appears to be one of the top performing flea and tick collars on the market for cats today. The 8-month protection vastly outpaces most other collars that need to be reapplied every 1-2 months. The waterproof design also makes Seresto a good choice for outdoor cats who swim or get baths. While Seresto is more expensive upfront than some other flea collars, the long-lasting protection means fewer reapplications over time. For cat owners wanting a set-it-and-forget-it solution to controlling fleas and ticks, Seresto is a recommended option to discuss with your veterinarian.

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