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NFA-VPS Over the Counter Companion Animal

Diptron 268 mg Spot-on Solution for Large Dogs

Active ingredient: Fipronil

Form

Spot-on

Species

Dogs

Manufacturer

Química de Munguía S.A. (Quimunsa)

VMD MA No.

45883/4005

What it's used for

immediate and persistent insecticidal efficacy and prevents new infestations by fleas up to a maximum of 5 weeks. The product prevents new infestations of...

Full indications, dosage and side effects ↓
View official SPC (PDF)

The prescription itself has a price. See what practices near you charge for a consultation and the written prescription fee.

Paying less for Fipronil

  1. 1

    Ask your vet for a written prescription

    They must provide one on request. Under the CMA Order the fee is capped at £21 from 2027.

  2. 2

    Fill it at a registered online retailer

    The CMA found online pharmacies 50–60% cheaper than practice dispensing on common medicines — typically £200–£300 a year.

Clinical information

Diptron 268 mg Spot-on Solution for Large Dogs — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

immediate and persistent insecticidal efficacy and prevents new infestations by fleas
up to a maximum of 5 weeks.
The product prevents new infestations of ticks from day 9
to day 23 after product application. The product has not demonstrated an immediate
acaricidal effect, if ticks of these species are present when the product is applied, all
the ticks may not be killed within the first 48 hours but they may be killed within a
week.
The product can be used as part of the strategy in the treatment of flea allergy
dermatitis (FAD), where this has been previously diagnosed by a veterinarian.
AN: 01453/2024 and 01524/2024Page 2 of 7
Dosage – 1 pipette of 2.68 ml per dog weighing over 20 kg and up to 40 kg
bodyweight
For dogs over 60 kg use two pipettes of 2.68 ml
Method of administration
Hold upright. Tap the narrow part of the pipette to ensure the contents are within the
main body of the pipette.
Break back the snap-off top from the spot-on pipette along the scored line. Part the
coat between the shoulder blades until the skin is visible. Place the tip of the pipette
on the skin and squeeze gently at one or two spots to empty its contents onto the
skin.
Care should be taken to avoid excessive wetting of the hair with the product since
this will cause a sticky appearance of hairs at the treatment spot. However, should
this occur, it will disappear within 24 hours post application.
In the absence of safety studies, the minimum treatment interval is 4 weeks.
In the absence of available data, the product should not be used in puppies less than
8 weeks of age (and/or weighing less than 2kg).
Do not use on sick (systemic diseases, fever…) or convalescent animals.
Do not use in rabbits, as adverse reactions and even death could occur.
This product is specifically developed for dogs. Do not use in cats, as this could lead
to overdosing.
Do not use in cases of hypersensitivity to the active substance or to any of the
excipients.
Target species: Dogs
Rare
(1 to 10 animals / 10,000
animals treated):
Transient cutaneous reactions at the application
site (skin discoloration, local alopecia, pruritus,
erythema, capillary bleeding) and general pruritus
or alopecia.
Very rare
(<1 animal / 10,000 animals
treated, including isolated
reports):
Hypersalivation, reversible neurological signs
(hyperaesthesia, depression, nervous signs),
vomiting or respiratory signs.
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian, to
either the marketing authorisation or the national competent authority via the national
reporting system. See the package leaflet for respective contact details.
AN: 01453/2024 and 01524/2024Page 4 of 7
The product does not prevent ticks from attaching to the animals. Therefore, the
transmission of infectious diseases by ticks cannot be excluded. There is no data
available on the effect of bath / shampoo on the efficacy of the veterinary drug in
dogs. Bathing / shampoo applied before or often after treatment may reduce the
effectiveness of the product.
Fleas from pets often infest the animal's basket, bedding and regular resting areas
such as carpets and soft furnishings which should be treated, in case of massive
infestation and at the beginning of the control measures, with a suitable insecticide
and vacuumed regularly.
When used as part of a strategy for the treatment of Flea Allergy Dermatitis, monthly
applications to the allergic patient and to other dogs in the household are
recommended.
To reduce re-infestation from emergence of new fleas, it is recommended that all
dogs in a household be treated. Other animals living in the same household should
also be treated with a suitable product.
The product will prevent new tick infestations from day 9 to day 23 after application of
the product. Considering that it takes 9 days to reach sufficient efficacy, there may be
gaps in the prevention of re-infestations after subsequent applications of the product.

Special precautions for safe use in the target species:
For external use only. Do not apply the product on wounds or damaged skin.
Avoid contact with the animal’s eyes. In case of accidental eye contact immediately
and thoroughly flush the eyes with water.
Animals should be weighed accurately prior to treatment (see section 3.3).
It is important to make sure that the product is applied to an area where the animal
cannot lick it off, and to make sure that animals do not lick each other following
treatment.
The potential toxicity of the product for puppies less than 8 weeks of age in contact
with a treated bitch is not documented. Special care should be taken in this case.
AN: 01453/2024 and 01524/2024Page 3 of 7
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
This product may cause neurotoxicity. Keep stored pipettes in the original packaging
until ready to use. In order to prevent children from getting access to used pipettes,
dispose of used pipettes immediately.
People with a known hypersensitivity to fipronil or any of the excipients should avoid
contact with the veterinary medicinal product.
This product can cause mucous membrane and eye irritation. Therefore, contact of
the product with mouth and eyes should be avoided. In case of accidental ocular
exposure or irritation of the eyes during administration, these should be rinsed
immediately and thoroughly with plain water. If eye irritation persists, seek medical
advice immediately and show the package leaflet or the label to the physician.
Avoid contents coming into contact with the fingers. In case of dermal exposure,
wash immediately with soap and water.
Wash hands after use.
Do not smoke, drink or eat during application.
Treated animals should not be handled, and children should not be allowed to play
with them until the application site is dry. It is therefore recommended that animals
are not treated during the day, but should be treated during the early evening, and
that recently treated animals should not be allowed to sleep with owners, especially
children.
Special precautions for the protection of the environment:
Fipronil may adversely affect aquatic organisms. Dogs should not be allowed to swim
in watercourses for 2 days after application.
Do not use simultaneously with other flea products which are applied directly onto the
animal.
Store in the original package.
Store below 30ºC.
AN: 01453/2024 and 01524/2024Page 6 of 7
Not applicable.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.

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