Best Flea Treatment for Dogs UK: How to Choose the Right Option
Not every flea treatment suits every dog. Compare formats, lifestyle fit, and what’s actually licensed for general sale vs prescription-only in the UK.
August 17, 2026
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Seresto Flea and Tick Control Collar for Dogs and Puppies
From £41.34
Seresto Flea and Tick Control Collar for Dogs and Puppies
From £41.34
For dogs and puppies
Seresto is a flea and tick collar for dogs, made by Elanco. Choose by weight: 38cm for dogs up to 8kg, 70cm for dogs over 8kg. Suitable for puppies aged 7 weeks and older.
- Fleas: 7 to 8 months’ protection
- Ticks: killed and repelled for 8 months
- Also treats biting lice
Use it as the product leaflet directs.
One collar per pack.
NFA-VPS: a vet, pharmacist or SQP must be satisfied it suits your dog before supply.
Order Monday to Friday before 14:00pm to guarantee next
day delivery.
Ordering Prescription-Only Products
This item requires a current prescription from your vet before we can dispatch it. The good news? Sorting it out is simple and only takes a moment.
- Select or register your pet
- Attach a clear image or PDF of the prescription
- Complete your order at checkout
As soon as your prescription reaches us, our team will verify the details and get your pet’s treatment posted out to you.
Order Monday to Friday before 14:00pm to guarantee next
day delivery.
Product Features
For dogs and puppies
Seresto is a flea and tick collar for dogs, made by Elanco. Choose by weight: 38cm for dogs up to 8kg, 70cm for dogs over 8kg. Suitable for puppies aged 7 weeks and older.
- Fleas: 7 to 8 months’ protection
- Ticks: killed and repelled for 8 months
- Also treats biting lice
Use it as the product leaflet directs.
One collar per pack.
NFA-VPS: a vet, pharmacist or SQP must be satisfied it suits your dog before supply.
Product Details
Seresto collar for dogs: 8 months of flea and tick control
Seresto is a slow-release collar containing two active ingredients. Imidacloprid kills adult fleas, flea larvae and biting lice (it blocks nerve signals in the parasite, causing paralysis). Flumethrin kills ticks and repels them, which helps stop them biting (it disrupts the tick’s nerve cells). Both spread from the collar across your dog’s skin and coat in low amounts while the collar is worn.
Safe use
Don’t sleep with a dog wearing the collar, especially children, and don’t let children play with it or put it in their mouths. Remove any ticks already attached when you fit the collar, and wash your hands with cold water afterwards.
Some dogs get itching, redness or hair loss under the collar. Side effects are listed in the official product information below.
Legal category: NFA-VPS
View the official product information: Small dogs (38cm) | Large dogs (70cm)
Instructions
Choose the collar by your dog’s weight: 38cm for dogs up to 8kg, 70cm for dogs over 8kg.
Use Seresto exactly as the product leaflet directs. Full directions for use: small dogs (38cm) | large dogs (70cm).
Ask your vet or pharmacist if you are unsure how to fit it.
Sizes
- Small dogs up to 8kg: 38cm collar
- Large dogs over 8kg: 70cm collar
Each pack contains one collar, sealed in its own bag. Seresto for cats is a separate product.
Key Benefits
- One collar covers fleas, ticks and biting lice for months, with no monthly treatment to remember
- Kills ticks before they usually feed
- Helps reduce the risk of two tick-borne diseases, babesiosis and ehrlichiosis, spread by the brown dog tick
- Stops flea larvae developing in your dog’s surroundings for 8 months
Seresto dog collar specification
| Starts working on fleas | Within 48 hours |
|---|---|
| Starts working on new ticks | Within 2 days |
| Water | Water-resistant |
| Shelf life | 5 years unopened |
| Legal category | NFA-VPS |
Ingredients
Active ingredients
38cm collar (small dogs): imidacloprid 1.25g and flumethrin 0.56g
70cm collar (large dogs): imidacloprid 4.5g and flumethrin 2.03g
Other ingredients
Also contains titanium dioxide (E171), iron oxide black (E172), dibutyladipate, propylene glycol dicaprylocaprate, epoxidised soybean oil, stearic acid and polyvinyl chloride.
How ordering works
No prescription needed for this item. A vet, pharmacist or SQP checks every order before it’s supplied.
Legal category: NFA-VPSChoose size and pack
Pick the weight band or pack size you need, then add to basket.
Check out in 3 steps
Delivery method, billing, payment. Free standard delivery over £50.
Packed and posted
Royal Mail Standard (2–3 working days) or 24 First Class (1 working day). Unbranded, secure packaging.
Frequently asked questions
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