On Defence Flea + Tick Spot-on Solution for Cats 50 mg/60 mg
Active ingredients: (S)-Methoprene, Fipronil
Form
Spot-on
Species
Manufacturer
Chanelle Pharmaceuticals Manufacturing Ltd
VMD MA No.
08749/3078
What it's used for
In cats: - To be used against infestations with fleas, alone or in association with ticks and/or biting lice. - Elimination of fleas (Ctenocephalides spp.)...
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Paying less for (S)-Methoprene + Fipronil
-
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.
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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.
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On Defence Flea + Tick Spot-on Solution for Cats 50 mg/60 mg — SPC Details
Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.
- To be used against infestations with fleas, alone or in association with ticks and/or
biting lice.
- Elimination of fleas (Ctenocephalides spp.). Insecticidal efficacy against new
infestations with adult fleas persists for 4 weeks. Prevention of the multiplication of
fleas by inhibiting the development of eggs (ovicidal activity), larvae and pupae
(larvicidal activity) originating from eggs laid by adult fleas for six weeks after
application.
- Elimination of ticks (Ixodes ricinus, Dermacentor variabilis, Rhipicephalus
sanguineus). The product has a persistent acaricidal efficacy for up to 2 weeks
against ticks (based on experimental data).
- Elimination of biting lice (Felicola subrostratus).
Revised: September 2025
AN: 01788/2025
mg/kg for fipronil and 6 mg/kg for (S)-methoprene, by topical application to the skin.
In the absence of safety studies, the minimum treatment interval is 4 weeks.
Method of administration:
Hold the pipette upright. Tap the narrow part of the pipette to ensure the contents
remain within the main body of the pipette. Snap back the tip. Part the coat on the
back of the animal at the base of the neck in front of the shoulder blades until the
skin is visible. Place the tip of the pipette on the skin and squeeze the pipette several
times to empty its contents completely and directly onto the skin in one spot.
Do not overdose.
8 weeks old and/or weighing less than 1 kg.
Do not use on sick (e.g. systemic diseases, fever) or convalescent animals.
Do not use in rabbits due to a risk of adverse drug reactions or even death.
In absence of studies, the use of the product is not recommended in non-target
species.
Do not use in known cases of hypersensitivity to the active substances or to any of
the excipients.
application site (scaling, local hair loss, itching, redness) and general itching or hair
loss have been reported after use.
Excessive salivation, reversible nervous signs (increased sensitivity to stimulation,
depression, other nervous signs) or vomiting have also been observed after use.
If licking occurs, a brief period of excessive salivation may be observed due mainly to
the nature of the carrier.
Special precautions for use in animals
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.
No data on the effect of bathing/shampooing on the efficacy of the product in cats is
available. However, based on information available for dogs shampooed as from 2
days after application of the product, it is not recommended to bath animals within 2
days after application of the product.
There may be an attachment of single ticks. For this reason a transmission of
infectious diseases cannot be completely excluded if conditions are unfavourable.
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.
The potential toxicity of the product for kittens of less than 8 weeks of age in contact
with a treated queen is not documented. Special care should be taken in this case.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
This product can cause mucous membrane, skin and eye irritation. Therefore,
contact of the product with mouth, skin and eyes should be avoided.
People with a known hypersensitivity to insecticides or alcohol should avoid contact
with the product. Avoid contents coming into contact with the fingers. If this occurs,
wash hands with soap and water.
After accidental ocular exposure the eye should be rinsed carefully with clean water.
If the product is accidently swallowed, seek medical advice immediately and show
the package leaflet to the physician.
Wash hands after use.
Treated animals should not be handled until the application site is dry, and children
should not be allowed to play with treated animals until the application site is dry. It is
therefore recommended that animals are not treated during the day, but should be
Revised: September 2025
AN: 01788/2025
treated during the early evening, and that recently treated animals are not allowed to
sleep with owners, especially children.
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.
Do not smoke, drink or eat during application.
Store in the original package.
4.9 Amounts to be administered and administration route
One pipette of 0.5 ml per cat, corresponding to a minimum recommended dose of 5
mg/kg for fipronil and 6 mg/kg for (S)-methoprene, by topical application to the skin.
In the absence of safety studies, the minimum treatment interval is 4 weeks.
Method of administration:
Hold the pipette upright. Tap the narrow part of the pipette to ensure the contents
remain within the main body of the pipette. Snap back the tip. Part the coat on the
back of the animal at the base of the neck in front of the shoulder blades until the
skin is visible. Place the tip of the pipette on the skin and squeeze the pipette several
times to empty its contents completely and directly onto the skin in one spot.
Do not overdose.
4.10 Overdose (symptoms, emergency procedures, antidotes), if necessary
The risk of experiencing adverse effects may increase with overdosing (see section
4.6).
No undesirable effects were observed in target animal safety studies in cats and
kittens aged 8 weeks and older and weighing about 1 kg treated once a month at five
times the recommended dose for six consecutive months.
Itching may occur following treatment.
Overdose application of the product will cause a sticky appearance of hairs at the
treatment spot. However, should this occur, it will disappear within 24 hours post
application.
Revised: September 2025
AN: 01788/2025
4.11 Withdrawal Period(s)
Not applicable.
5.
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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Other Products Containing (S)-Methoprene
These products share the same active ingredient and may be suitable alternatives. Always consult your vet.
Bob Martin Clear Plus 134 mg/ 120.6 mg Spot-on Solution for Medium Dogs
AVM-GSLPets Choice Limited
Bob Martin Clear Plus 134 mg/ 120.6 mg Spot-on Solution for Medium Dogs
AVM-GSLPets Choice Healthcare Limited
Bob Martin Clear Plus 268 mg/ 241.2 mg Spot-on Solution for Large Dogs
AVM-GSLPets Choice Limited
Bob Martin Clear Plus 268 mg/ 241.2 mg Spot-on Solution for Large Dogs
AVM-GSLPets Choice Healthcare Limited
Bob Martin Clear Plus 402 mg/ 361.8 mg Spot-on Solution for Extra Large Dogs
AVM-GSLPets Choice Limited
Bob Martin Clear Plus 402 mg/ 361.8 mg Spot-on Solution for Extra Large Dogs
AVM-GSLPets Choice Healthcare Limited
Alternative options to consider
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