Seresto is a long-lasting flea and tick collar manufactured by Elanco (formerly Bayer) that provides up to 8 months of continuous protection. It contains imidacloprid (kills fleas) and flumethrin (repels and kills ticks). It is one of the most cost-effective flea and tick prevention methods available in the UK.

Price Comparison

  • From your vet: £30–£45
  • Online pharmacies/retailers: £20–£32
  • Cost per month (8-month collar): £2.50–£5.60 from online retailers vs £3.75–£5.60 from your vet

Seresto is unique among flea treatments because it is classified as NFA-VPS (non-food animal – veterinarian, pharmacist, SQP), meaning you do not need a vet prescription to buy it. You can purchase from pharmacies, registered online retailers, and pet shops with a Suitably Qualified Person (SQP).

What Does Seresto Protect Against?

  • Fleas: Kills and repels fleas for 7–8 months
  • Ticks: Kills and repels ticks for 8 months
  • Flea larvae: Active ingredient released into the coat kills larvae in the environment around your pet
  • Biting lice: Treatment of lice infestations in dogs

Species and Forms

  • Dogs: Two sizes — small dogs (up to 8kg) and large dogs (over 8kg)
  • Cats: Single size for all cats (38cm collar)

Side Effects

  • Mild skin irritation or hair loss under the collar — usually temporary and resolves as the animal adjusts
  • Occasional itching at the collar site in the first few days
  • Very rare allergic reactions
  • Remove if your pet swims frequently — water exposure reduces the collar's longevity
  • Ensure the collar is fitted correctly with a two-finger gap to prevent rubbing

Prescription Requirements

Seresto does not require a veterinary prescription. It is NFA-VPS, so you can buy it from any pharmacy, registered online retailer, or pet shop with an SQP. This makes it one of the easiest flea treatments to buy without a vet visit.

Seresto vs Monthly Treatments

  • Seresto (8 months): £20–£32 = £2.50–£4 per month
  • NexGard Spectra (monthly): £8–£13 per month from online pharmacies (but includes wormer)
  • Bravecto (12 weeks): £5–£9 per month from online pharmacies
  • Frontline Plus (monthly): £3–£6 per month (NFA-VPS, no prescription)

Seresto is competitive on price and unbeatable on convenience — one collar lasts most of the year.

How to Save

  • Buy online: No prescription needed — shop around for the best price
  • Beware counterfeits: Buy only from authorised retailers. Counterfeit Seresto collars are a known problem
  • Compare prices: Use VetCost to compare across retailers

Last updated: March 2026. Sources: VMD product datasheet, CMA provisional decision (October 2025), VetCost data.