Deosect Fly & Lice Control Solution for Horses

Deosect Fly & Lice Control Solution for Horses
Product image
250ml Bottle
1 Litre Bottle

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  • 250ml Bottle £43.39
  • 1 Litre Bottle £90.12

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Description

A powerful and effective residual insecticide, Deosect, produced by Zoetis, is specially developed for the control of flies and lice on horses. sweet itch horses can be plagued by midges.

Not suitable for use on any animals for human consumption. POM-VPS

Please note: As this is a flammable product it cannot be sent via Royal Mail so will incur a delivery charge.

We recommend you undertake a patch test before using on your horses. Deosect must be diluted prior to use and according to the manufacturers instructions.

Need help or advice? Contact us:


All prices include VAT where applicable.

Medication Datasheets

Reviews (205)

Summary of Reviews for Deosect Fly & Lice Control Solution for Horses

Overall 5
Value For Money
Quality/Durability
Pet's Opinion
195 out of 205 (95%) customers would recommend this product.
5 stars (155 reviews)
4 stars (34 reviews)
3 stars (6 reviews)
2 stars (7 reviews)
1 stars (3 reviews)

Only verified purchasers of this product can leave a review.

55 Needed!
Verified Purchase

By on 11 May 2026

Works amazing, finally the pony is free of liceSmells very strong

Customer recommends this product

55 Brilliant product
Verified Purchase

By on 25 April 2026

My horse didn't have lice but had to do the whole herd, kept the lice off him

Customer recommends this product

45 Used for lice.
Verified Purchase

By on 17 April 2026

Recommended this product to treat suspected lice. Used as directed and skin is now clear.

Customer recommends this product

55 Deosect
Verified Purchase

By on 12 April 2026

This product works amazing first time I e used it

Customer recommends this product

45 I purchased this product to deal with a suspected lice problem in one of my horses.
Verified Purchase

By on 7 April 2026

Having followed the instructions to the letter and I’ve now administered two applications I fairly certain the problem has been addressed successfully.Easy to use in either a spray applicator or by sponge.

Customer recommends this product

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Q & A

Below are some recent questions we've received regarding Deosect Fly & Lice Control Solution for Horses, including answers from our team.

25 September 2025 at 7:11am

Fleas

Williams

Is this effective on fleas

  • VioVet Staff

Deosect Fly & Lice Control Solution for Horses” is not officially labelled for fleas (on horses or other species), so using it for fleas is off-licence and might not be effective or appropriate. Use a flea treatment specifically labelled for fleas on the species involved.

13 June 2025 at 7:57pm

Fly treatment in horses

Sara Barton-Dodson

  • VioVet customer since 2021
  • From: Kent, United Kingdom

How do I apply

  • VioVet Staff

Deosect Application Instructions (for Horses)

1. Dilution

  • Deosect must be diluted 1:50 with water.

  • That means 10 ml of Deosect per 500 ml of water.

Common dilution examples:

Amount of Deosect Amount of Water Final Volume
10 ml 500 ml 510 ml
20 ml 1 litre 1.02 L
50 ml 2.5 litres 2.55 L
10 May 2025 at 10:13am

Shelf life once opened

Susie

Hi,
What is the shelf life of undiluted deosect once opened?

  • VioVet Staff

The solution should be used within 24 hours.

12 April 2025 at 12:42pm

How long does each application last

Claire Jones

  • VioVet customer since 2017
  • From: Gloucestershire, United Kingdom

How long does each application last please

  • VioVet Staff

Deosect, when used as directed for fly and midge control, provides protection for up to 4 weeks. For lice control, it needs to be reapplied if necessary, with a minimum of 14 days between applications. Once diluted, the solution should be used within 24 hours

12 April 2025 at 10:08am

How long does each application last

Claire Jones

  • VioVet customer since 2017
  • From: Gloucestershire, United Kingdom

How long does each application last please

  • VioVet Staff

The Deosect Fly & Lice Control Solution for Horses provides effective control against flies and lice for up to 4 weeks per application .

21 January 2025 at 7:11pm

Application of the producy

Terri

Do you just need to spray this (once diluted) on top of the hair or does it need to be brushed in after spraying?

  • VioVet Staff

You just need to spray the solution onto the coat.

7 May 2023 at 9:18pm

Black flies on mare’s udder?

Shelagh

My 24 year old mare Hattie seems to be plagued more every summer with black flies on her udder. She has never had a foal. I keep the area scrupulously clean and use anti itch lotions on her tail but actually stopping flies biting her udder is very difficult.
I use Deosect on both my horses but Hattie is not very happy with it - gets into a real tizz when I apply it to her so I’m
uncertain as to whether I should use it on her udder or whether that area is too sensitive as there is no hair. I’d be glad of any advice. Thanks.

  • VioVet Staff

The datasheet for this medication states Careful attention must be paid to total animal coverage, especially the face, legs, back and hind quarters with the caveat Do not apply to any lesions where the skin is broken. This means it should be safe on any areas with intact skin, including the udder. The datasheet actually advises full body coverage.

If the flies have caused inflammation or bites then the skin may be broken which could be the cause of the signs you describe. It is worth inspecting the area to make sure this is not the case.
Otherwise there will be a slightly cool sensation when the product is applied to the skin and it may be this that your horse finds disconcerting.

I suggest applying just water to your horse and monitoring her reaction. If the response is similar and the skin appears normal then it may be behavioural, in which case try to train her to get used to the experience if possible.

6 April 2023 at 11:30am

Horse mites

Catherine miller

This product is it any good for my horse witch l think could have mites

  • VioVet Staff

This medication is licensed to treat flies and lice only, not mites. It is therefore not advised for this use. If you would like advice on what products can treat mites in your horse then it is recommended to get in touch with your vet as most require a prescription. You can also get in touch with us at [email protected].

7 September 2022 at 11:20am

Minimum age for use of product

Maria

Hello, what is the minimum age the product can be used on? I read online not for use under 3 weeks of age but cannot see this information on the data sheet. Many thanks!

  • VioVet Staff

Deosect is not licensed for use in animals less than 12 months old as there is no studied dose below this, any use on the foal itself would be alongside a risk vs. benefit analysis by your vet.

30 August 2022 at 12:27pm

How much can you apply

Maximum usage ?

Good Afternoon ..
Can you apply this product daily ... ?

  • VioVet Staff

The datasheet for this medication states the following regarding application:

Fly Control

The application of the solution should commence at the onset of the fly season and be repeated monthly for general fly control and every two weeks for severe head and face fly control.

Lice Control

Apply when lice are observed and repeat as necessary at a minimum interval of 14 days.

Daily use would be off license and unfortunately this means we cannot advise on it. Your local vet may be able to discuss this further with you though, however daily application is unlikely to improve the effectiveness of the product.

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