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POM-V Prescription Required Companion Animal

Duowin, Cutaneous Spray, Solution

Active ingredients: Permethrin (Cis:Trans 40:60), Pyriproxyfen

Form

Spray

Species

Dogs

Manufacturer

Virbac

VMD MA No.

05653/4046

What it's used for

Treatment and prevention of flea (Ctenocephalides felis) and tick (Rhipicephalus sanguineus, Ixodes ricinus) infestations. Against fleas: Treatment and pre...

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

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Prescription required

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Clinical information

Duowin, Cutaneous Spray, Solution — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.

Treatment and prevention of flea (Ctenocephalides felis) and tick (Rhipicephalus
sanguineus, Ixodes ricinus) infestations.
Against fleas:
Treatment and prevention of a new infestation by adult fleas for 6 weeks.
Prevention of flea multiplication for 10 weeks by sterilizing the eggs.
Against ticks:
Treatment and prevention of a new infestation for 4 weeks.
For external use only.
One pump activation delivers approximately 3.0 ml.
The dosage is 5 ml of solution per kg bodyweight which can be achieved by 5 pump
activations for 3 kg bodyweight.
This is equivalent to 94 mg Permethrin and 1 mg Pyriproxyfen per kg bodyweight.
Weight of dog3 kg7 kg10 kg15 kg20 kg30 kg40 kgNumber of pump
activations5121725345067
Spray onto the animal haircoat (avoiding the eyes) in order to wet it entirely. While
spraying, ruffle the coat and apply against the lay of the hair so that the product
penetrates down to the skin. Care should be taken to avoid spraying into the eyes of
the animal. Allow the product to dry naturally without wiping the coat.
Do not wash or shampoo dogs after treatment.
Should you need to shampoo your dog, it is recommended to renew the application
of the product afterwards in order to maintain the protection against flea and tick
infestation.
Dogs which have been repeatedly exposed to heavy rain or which enter water
frequently should be retreated.
The product is a Prescription Only Medicine which can be used according to parasite
pressure.
Retreatment may be advised at monthly intervals in case of strong flea infestation.

Revised October 2017
AN: 00673/2017
Do not use on cats as adverse reactions and even death can occur.
See also sections 4.5. and 4.7.
Rare cases of pruritus, gastrointestinal signs or behavioural changes (agitation or
apathy), have been observed which disappear rapidly without treatment.
In very rare occasions, dogs may show neurological symptoms such as tremors and
hypersalivation.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals treated displaying adverse reaction(s))
- common (more than 1 but less than 10 animals in 100 animals treated)
- uncommon (more than 1 but less than 10 animals in 1,000 animals treated)
- rare (more than 1 but less than 10 animals in 10,000 animals treated)
- very rare (less than 1 animal in 10,000 animals treated, including isolated reports).
FLAMMABLE.
Keep treated animals away from fires and other sources of heat for at least 30
minutes following spraying and until the fur is totally dry.
Underdosing should be avoided in order to maintain the claimed duration of efficacy.
Care should be taken to accurately weigh the animal and to comply with the
recommended number of activations of the pump as DUOWIN is being applied.

Revised October 2017
AN: 00673/2017
If signs of disease persist or appear consult your veterinary surgeon or veterinary
practitioner.
Fleas from pets often infest the animal's basket, bedding and regular resting areas
such as carpets and soft furnishings which should be treated with a suitable
insecticide and vacuumed regularly. This will aid reduction in environmental
challenge and maximise the duration of protection against re-infestation given by
DUOWIN.

i/ Special precautions for use in animals
Do not use on puppies under 2 months of age.
Do not use on sick or convalescent dogs.
Do not use on cats as adverse reactions and even death can occur.
Prevent treated animals from licking or grooming themselves, and in multianimal
households prevent
other animals from grooming treated dogs, at least until the coat is dry.
This product is extremely poisonous to cats and could be fatal due to the unique
physiology of cats who are unable to metabolise the amount of permethrin contained
in Duowin Spray. Symptoms are severe ; seizures and ataxia which can result in cat
death.
To prevent accidental contact with Duowin Spray keep cats away from treated dogs
until hair coat is dry. It is important to ensure that cats do not lick off the solution from
treated dogs.
Life-threatening poisoning may occur. In case of accidental dermal exposure, wash
the cat with shampoo or soap, and seek veterinary advice rapidly. To prevent cats
from being accidentally exposed to the product, keep treated dogs away from cats
after treatment until the application site is dry. It is important to ensure that cats do
not groom the site of application on a dog, which has been treated with this product.
In case of exposure of this type, seek veterinary advice immediately if this occurs.
ii/ Special precautions to be taken by the person administering the veterinary
medicinal product to animals
Use impervious household gloves (e.g.: rubber neoprene or vinyl) when using the
product.
Do not spray on naked flame or any incandescent material.
FLAMMABLE.
Do not smoke, drink or eat while handling the product.
Do not inhale spray mist. Use only in well ventilated areas.
Avoid contact with skin and eyes. Wash hands and exposed skin thoroughly after
use.
In case of accidental eye contact, flush eyes abundantly with water.
Keep away from food or drink.
Avoid prolonged exposure.
iii/ Other precautions
Do not allow dogs to enter ponds or streams on the day they have been treated.

Revised October 2017
AN: 00673/2017
Do not use any other ectoparasiticide in conjunction with Duowin.
FLAMMABLE.
Keep treated animals away from fires and other sources of heat for at least 30
minutes following spraying and until the fur is totally dry.
Underdosing should be avoided in order to maintain the claimed duration of efficacy.
Care should be taken to accurately weigh the animal and to comply with the
recommended number of activations of the pump as DUOWIN is being applied.

Revised October 2017
AN: 00673/2017
If signs of disease persist or appear consult your veterinary surgeon or veterinary
practitioner.
Fleas from pets often infest the animal's basket, bedding and regular resting areas
such as carpets and soft furnishings which should be treated with a suitable
insecticide and vacuumed regularly. This will aid reduction in environmental
challenge and maximise the duration of protection against re-infestation given by
DUOWIN.
4.5 Special precautions for use
i/ Special precautions for use in animals
Do not use on puppies under 2 months of age.
Do not use on sick or convalescent dogs.
Do not use on cats as adverse reactions and even death can occur.
Prevent treated animals from licking or grooming themselves, and in multianimal
households prevent
other animals from grooming treated dogs, at least until the coat is dry.
This product is extremely poisonous to cats and could be fatal due to the unique
physiology of cats who are unable to metabolise the amount of permethrin contained
in Duowin Spray. Symptoms are severe ; seizures and ataxia which can result in cat
death.
To prevent accidental contact with Duowin Spray keep cats away from treated dogs
until hair coat is dry. It is important to ensure that cats do not lick off the solution from
treated dogs.
Life-threatening poisoning may occur. In case of accidental dermal exposure, wash
the cat with shampoo or soap, and seek veterinary advice rapidly. To prevent cats
from being accidentally exposed to the product, keep treated dogs away from cats
after treatment until the application site is dry. It is important to ensure that cats do
not groom the site of application on a dog, which has been treated with this product.
In case of exposure of this type, seek veterinary advice immediately if this occurs.
ii/ Special precautions to be taken by the person administering the veterinary
medicinal product to animals
Use impervious household gloves (e.g.: rubber neoprene or vinyl) when using the
product.
Do not spray on naked flame or any incandescent material.
FLAMMABLE.
Do not smoke, drink or eat while handling the product.
Do not inhale spray mist. Use only in well ventilated areas.
Avoid contact with skin and eyes. Wash hands and exposed skin thoroughly after
use.
In case of accidental eye contact, flush eyes abundantly with water.
Keep away from food or drink.
Avoid prolonged exposure.
iii/ Other precautions
Do not allow dogs to enter ponds or streams on the day they have been treated.

Revised October 2017
AN: 00673/2017
4.6 Adverse reactions (frequency and seriousness)
Rare cases of pruritus, gastrointestinal signs or behavioural changes (agitation or
apathy), have been observed which disappear rapidly without treatment.
In very rare occasions, dogs may show neurological symptoms such as tremors and
hypersalivation.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals treated displaying adverse reaction(s))
- common (more than 1 but less than 10 animals in 100 animals treated)
- uncommon (more than 1 but less than 10 animals in 1,000 animals treated)
- rare (more than 1 but less than 10 animals in 10,000 animals treated)
- very rare (less than 1 animal in 10,000 animals treated, including isolated reports).
4.7 Use during pregnancy, lactation or lay
Do not use on nursing bitches.
Consult your veterinary surgeon for appropriate treatment of flea and tick infestations
in puppies and nursing bitches.
4.8 Interaction with other medicinal products and other forms of interaction
Do not use any other ectoparasiticide in conjunction with Duowin.
4.9 Amounts to be administered and administration route
For external use only.
One pump activation delivers approximately 3.0 ml.
The dosage is 5 ml of solution per kg bodyweight which can be achieved by 5 pump
activations for 3 kg bodyweight.
This is equivalent to 94 mg Permethrin and 1 mg Pyriproxyfen per kg bodyweight.
Weight of dog3 kg7 kg10 kg15 kg20 kg30 kg40 kgNumber of pump
activations5121725345067
Spray onto the animal haircoat (avoiding the eyes) in order to wet it entirely. While
spraying, ruffle the coat and apply against the lay of the hair so that the product
penetrates down to the skin. Care should be taken to avoid spraying into the eyes of
the animal. Allow the product to dry naturally without wiping the coat.
Do not wash or shampoo dogs after treatment.
Should you need to shampoo your dog, it is recommended to renew the application
of the product afterwards in order to maintain the protection against flea and tick
infestation.
Dogs which have been repeatedly exposed to heavy rain or which enter water
frequently should be retreated.
The product is a Prescription Only Medicine which can be used according to parasite
pressure.
Retreatment may be advised at monthly intervals in case of strong flea infestation.

Revised October 2017
AN: 00673/2017
4.10 Overdose (symptoms, emergency procedures, antidotes), if necessary
A tolerance study performed on puppies from 2 months of age at 5 times the
recommended dosage showed no adverse reactions. However, should signs of
intolerance occur (hyperaesthesia, ataxia, erythema, tremors), shampoo the dog
thoroughly and repeatedly in order to eliminate the product.
In case of more severe signs of poisoning (convulsions), immediate symptomatic
treatment should be undertaken under veterinary surveillance. No specific antidote to
permethrin is known, however neurological symptoms should be treated e.g. with
atropine and anti-convulsivant agents.
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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