Ridamax 80 mg + 8 mg Spot-on Solution for Large Cats
Active ingredients: Imidacloprid, Moxidectin
Form
Spot-on
Species
Manufacturer
Chanelle Pharmaceuticals Manufacturing Ltd
VMD MA No.
08749/5047
What it's used for
For cats suffering from, or at risk from, mixed parasitic infections: • the treatment and prevention of flea infestation (Ctenocephalides felis), • the tre...
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Ridamax 80 mg + 8 mg Spot-on Solution for Large Cats — SPC Details
Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.
• the treatment and prevention of flea infestation (Ctenocephalides felis),
• the treatment of ear mite infestation (Otodectes cynotis),
• the treatment of notoedric mange (Notoedres cati),
• the treatment of the lungworm Eucoleus aerophilus (syn. Capillaria
aerophila) (adults),
• the prevention of lungworm disease (L3/L4 larvae of Aelurostrongylus
abstrusus),
• the treatment of the lungworm Aelurostrongylus abstrusus
• the treatment of the eye worm Thelazia callipaeda
Issued: January 2024
AN: 01889/2022
• the prevention of heartworm disease (L3 and L4 larvae of Dirofilaria
immitis),
• the treatment of infections with gastrointestinal nematodes (L4 larvae,
immature adults and adults of Toxocara cati and
tubaeforme
The veterinary medicinal product can be used as part of a treatment strategy for flea
allergy dermatitis (FAD).
The recommended minimum doses are 10 mg/kg bodyweight imidacloprid and 1.0
mg/kg bodyweight moxidectin, equivalent to 0.1 ml/kg bodyweight of the veterinary
medicinal product.
Underdosing could result in ineffective use and may favour resistance development.
To ensure a correct dosage, body weight should be determined as accurately as
possible. For infestations/infections with the indicated parasites, the need for and
frequency of re-treatment(s) should be based on professional advice and should take
into account the local epidemiological situation and the animal’s lifestyle.
Weight of
cat [kg]
Pipette size to be
used
Volume
[ml]
Imidacloprid
[mg/kg bw]
Moxidectin
[mg/kg bw]
> 4–8 kgRidamax for large cats0.810–201–2
Flea treatment and prevention (Ctenocephalides felis)
One treatment prevents future flea infestation for 4 weeks. Existing pupae in the
environment may emerge for 6 weeks or longer after treatment is initiated, depending
upon climatic conditions. Therefore, it may be necessary to combine animal
treatment with environmental treatments aimed at breaking the flea life cycle in the
surroundings. This can result in a more rapid reduction in the household flea
population. The veterinary medicinal product should be administered at monthly
intervals when used as part of a treatment strategy for flea allergy dermatitis.
Treatment of ear mite infestation (Otodectes cynotis)
A single dose of the veterinary medicinal product should be administered. A further
veterinary examination 30 days after treatment is recommended as some animals
may require a second treatment. Do not apply directly to the ear canal.
Treatment of notoedric mange (Notoedres cati)
A single dose of the veterinary medicinal product should be administered.
Treatment of the lungworm Eucoleus aerophilus (syn. Capillaria aerophila) (adults)
A single dose of the veterinary medicinal product should be administered.
Prevention of Aelurostrongylus abstrusus
The veterinary medicinal product should be administered monthly.
Treatment of Aelurostrongylus abstrusus
The veterinary medicinal product should be administered monthly for three
consecutive months.
Treatment of the eye worm Thelazia callipaeda (adults)
A single dose of the veterinary medicinal product should be administered.
Heartworm prevention (Dirofilaria immitis)
Issued: January 2024
AN: 01889/2022
Cats in areas endemic for heartworm, or those which have travelled to endemic
areas, may be infected with adult heartworms. Therefore prior to treatment with the
veterinary medicinal product, the advice provided in section 4.5 should be
considered.
For prevention of heartworm disease, the veterinary medicinal product must be
applied at regular monthly intervals during the time of the year when mosquitoes (the
intermediate hosts which carry and transmit heartworm larvae) are present. The
veterinary medicinal product may be administered throughout the year. The first dose
may be given after first possible exposure to mosquitoes, but not more than one
month after this exposure. Treatment should continue at regular monthly intervals
until 1 month after the last exposure to mosquitoes. To establish a treatment routine,
it is recommended that the same day or date be used each month. When replacing
another heartworm preventative product in a heartworm prevention programme, the
first treatment with the veterinary medicinal product must be given within 1 month of
the last dose of the former medication.
In non-endemic areas there should be no risk of cats having heartworm. Therefore,
they can be treated without special precautions.
Roundworm and hookworm treatment (Toxocara cati and Ancylostoma tubaeforme)
In areas endemic for heartworm, monthly treatment may significantly reduce the risk
of re-infection caused by the respective roundworms and hookworms. In areas non-
endemic for heartworm, the product can be used as part of a seasonal prevention
programme against fleas and gastrointestinal nematodes.
Method of administration
Spot-on use.
For external use only.
Remove one pipette from the package. Tap the narrow part of the pipette to ensure
the contents are within the main body of the pipette. Snap back the tip of the pipette
to enable the contents to be expelled.
Part the fur on the animal's neck at the base of the skull until the skin is visible. Place
the tip of the pipette on the skin and squeeze the pipette firmly several times to empty
its contents directly onto the skin. Application at the base of the skull will minimise the
opportunity for the animal to lick the product. Apply only to undamaged skin.
Issued: January 2024
AN: 01889/2022
Do not use in case of hypersensitivity to the active substances or to any of the
excipients.
For ferrets: do not use Ridamax for dogs. Only “Ridamax for small cats and ferrets”
(0.4 ml) must be used.
For dogs, the corresponding “Ridamax for dog” product, which contains 100 mg/ml
imidacloprid and 25 mg/ml moxidectin, must be used.
Do not use on canaries.
Rare (1 to 10 animals / 10,000 animals
treated):
Application site greasy fur
Erythema
Vomiting
Hypersensitivity reaction
Very rare
(<1 animal / 10,000 animals treated,
including
isolated reports):
Neurological signs
Lethargy
, Inappetence
Agitation
‘Undetermined frequency (cannot be
estimated from the available data):
Pruritus
1
These signs disappear without further treatment.
These signs are mostly transient and can occur if the animal licks the application
site after treatment.
Transient.
The veterinary medicinal product tastes bitter. Salivation may occasionally occur if
the animal licks the application site immediately after treatment. This is not a sign of
intoxication and disappears within some minutes without treatment. Correct
application will minimise licking of the application site.
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 holder or its local representative or the national
competent authority via the national reporting system. See also section 16 of the
package leaflet for contact details.
Brief contact of the animal with water on one or two occasions between monthly
treatments is unlikely to significantly reduce the efficacy of the product. However,
frequent shampooing or immersion of the animal in water after treatment may reduce
the efficacy of the veterinary medicinal product.
Unnecessary use of antiparasitics or use deviating from the instructions given in the
SPC may increase the resistance selection pressure and lead to reduced efficacy.
The decision to use the product should be based on confirmation of the parasitic
species and burden, or of the risk of infection/infestation based on its epidemiological
features, for each individual animal.
The use of the veterinary medicinal product should be based on the confirmed
diagnosis of mixed infection (or risk of infection, where prevention applies) at the
same time (see also sections 4.2 and 4.9).
Special precautions for use in animals
The treatment of cats weighing less than 1 kg should be based on a benefit-risk
assessment.
There is limited experience on the use of the veterinary medicinal product in sick and
debilitated animals, thus the veterinary medicinal product should only be used based
on a benefit-risk assessment for these animals.
Do not apply in the mouth, in the eyes or the ears of the animal.
Issued: January 2024
AN: 01889/2022
Care should be taken that the veterinary medicinal product is not ingested by animals
and does not come into contact with the eyes or mouth of the recipient and/or other
animals.
Consider carefully the correct application method described in section 4.9, especially
that the veterinary medicinal product should be applied to the site specified in order
to minimise the risk for the animal to lick the veterinary medicinal product.
Do not allow recently treated animals to groom each other. Do not allow treated
animals to come into contact with untreated animals until the application site is dry.
In case of accidental oral uptake, symptomatic treatment should be administered.
There is no known specific antidote. The use of activated charcoal may be beneficial.
It is recommended that cats living in, or travelling to areas endemic for heartworm are
treated monthly with the veterinary medicinal product to protect them from heartworm
disease.
Whilst the accuracy of diagnosis of heartworm infection is limited, it is recommended
that attempts be made to check the heartworm status of any cat aged over 6 months,
before beginning prophylactic treatment, as use of the veterinary medicinal product
on cats which have adult heartworms may cause serious adverse effects, including
death. If adult heartworm infection is diagnosed, the infection should be treated in
accordance with current scientific knowledge.
In certain individual cats Notoedres cati infestation may be severe. In these severe
cases concomitant supportive treatment is necessary as treatment with the veterinary
medicinal product alone may not be sufficient to prevent death of the animal.
Imidacloprid is toxic for birds, especially canaries.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
People with known hypersensitivity to benzyl alcohol, imidacloprid or moxidectin
should administer this product with caution. In very rare cases this product may
cause skin sensitisation or transient skin reactions (for example numbness, irritation
or burning/tingling sensation).
In very rare cases this product may cause respiratory irritation in sensitive individuals.
In order to prevent children getting access to pipettes, keep the pipette in the original
packaging until ready for use and dispose of used pipettes immediately.
Avoid contact with skin, eyes or mouth.
Do not eat, drink or smoke during application.
Wash hands thoroughly after use.
After application do not stroke or groom animals until the application site is dry.
This may be ensured by treating animals in the evening. Do not allow recently
treated animals to sleep with owners, especially children.
In case of accidental spillage onto skin, wash off immediately with soap and water.
If the product accidentally gets into eyes, they should be thoroughly flushed with
water.
If skin or eye symptoms persist, or the product is accidentally swallowed, seek
medical advice immediately and show the package leaflet or the label to the
physician.
Issued: January 2024
AN: 01889/2022
Special precautions for the protection of the environment:
Not applicable.
Other precautions
The solvent in the veterinary medicinal product may stain or damage certain materials
including leather, fabrics, plastics and finished surfaces. Allow the application site to
dry before permitting contact with such materials.
macrocyclic lactone should be administered.
No interactions are expected between the veterinary medicinal product and routinely
used veterinary medicinal products or medical or surgical procedures.
Issued: January 2024
AN: 01889/2022
Do not store above 25°C.
treatments is unlikely to significantly reduce the efficacy of the product. However,
frequent shampooing or immersion of the animal in water after treatment may reduce
the efficacy of the veterinary medicinal product.
Unnecessary use of antiparasitics or use deviating from the instructions given in the
SPC may increase the resistance selection pressure and lead to reduced efficacy.
The decision to use the product should be based on confirmation of the parasitic
species and burden, or of the risk of infection/infestation based on its epidemiological
features, for each individual animal.
The use of the veterinary medicinal product should be based on the confirmed
diagnosis of mixed infection (or risk of infection, where prevention applies) at the
same time (see also sections 4.2 and 4.9).
4.5 Special precautions for use
Special precautions for use in animals
The treatment of cats weighing less than 1 kg should be based on a benefit-risk
assessment.
There is limited experience on the use of the veterinary medicinal product in sick and
debilitated animals, thus the veterinary medicinal product should only be used based
on a benefit-risk assessment for these animals.
Do not apply in the mouth, in the eyes or the ears of the animal.
Issued: January 2024
AN: 01889/2022
Care should be taken that the veterinary medicinal product is not ingested by animals
and does not come into contact with the eyes or mouth of the recipient and/or other
animals.
Consider carefully the correct application method described in section 4.9, especially
that the veterinary medicinal product should be applied to the site specified in order
to minimise the risk for the animal to lick the veterinary medicinal product.
Do not allow recently treated animals to groom each other. Do not allow treated
animals to come into contact with untreated animals until the application site is dry.
In case of accidental oral uptake, symptomatic treatment should be administered.
There is no known specific antidote. The use of activated charcoal may be beneficial.
It is recommended that cats living in, or travelling to areas endemic for heartworm are
treated monthly with the veterinary medicinal product to protect them from heartworm
disease.
Whilst the accuracy of diagnosis of heartworm infection is limited, it is recommended
that attempts be made to check the heartworm status of any cat aged over 6 months,
before beginning prophylactic treatment, as use of the veterinary medicinal product
on cats which have adult heartworms may cause serious adverse effects, including
death. If adult heartworm infection is diagnosed, the infection should be treated in
accordance with current scientific knowledge.
In certain individual cats Notoedres cati infestation may be severe. In these severe
cases concomitant supportive treatment is necessary as treatment with the veterinary
medicinal product alone may not be sufficient to prevent death of the animal.
Imidacloprid is toxic for birds, especially canaries.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
People with known hypersensitivity to benzyl alcohol, imidacloprid or moxidectin
should administer this product with caution. In very rare cases this product may
cause skin sensitisation or transient skin reactions (for example numbness, irritation
or burning/tingling sensation).
In very rare cases this product may cause respiratory irritation in sensitive individuals.
In order to prevent children getting access to pipettes, keep the pipette in the original
packaging until ready for use and dispose of used pipettes immediately.
Avoid contact with skin, eyes or mouth.
Do not eat, drink or smoke during application.
Wash hands thoroughly after use.
After application do not stroke or groom animals until the application site is dry.
This may be ensured by treating animals in the evening. Do not allow recently
treated animals to sleep with owners, especially children.
In case of accidental spillage onto skin, wash off immediately with soap and water.
If the product accidentally gets into eyes, they should be thoroughly flushed with
water.
If skin or eye symptoms persist, or the product is accidentally swallowed, seek
medical advice immediately and show the package leaflet or the label to the
physician.
Issued: January 2024
AN: 01889/2022
Special precautions for the protection of the environment:
Not applicable.
Other precautions
The solvent in the veterinary medicinal product may stain or damage certain materials
including leather, fabrics, plastics and finished surfaces. Allow the application site to
dry before permitting contact with such materials.
4.6 Adverse reactions (frequency and seriousness)
Cats
Rare (1 to 10 animals / 10,000 animals
treated):
Application site greasy fur
Erythema
Vomiting
Hypersensitivity reaction
Very rare
(<1 animal / 10,000 animals treated,
including
isolated reports):
Neurological signs
Lethargy
, Inappetence
Agitation
‘Undetermined frequency (cannot be
estimated from the available data):
Pruritus
1
These signs disappear without further treatment.
These signs are mostly transient and can occur if the animal licks the application
site after treatment.
Transient.
The veterinary medicinal product tastes bitter. Salivation may occasionally occur if
the animal licks the application site immediately after treatment. This is not a sign of
intoxication and disappears within some minutes without treatment. Correct
application will minimise licking of the application site.
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 holder or its local representative or the national
competent authority via the national reporting system. See also section 16 of the
package leaflet for contact details.
4.7 Use during pregnancy, lactation or lay
The safety of the veterinary medicinal product has not been established during
pregnancy and lactation in the target species. Therefore, the use of the product is not
recommended in animals intended for breeding or during pregnancy and lactation.
4.8 Interaction with other medicinal products and other forms of interaction
During treatment with the veterinary medicinal product no other antiparasitic
macrocyclic lactone should be administered.
No interactions are expected between the veterinary medicinal product and routinely
used veterinary medicinal products or medical or surgical procedures.
Issued: January 2024
AN: 01889/2022
4.9 Amounts to be administered and administration route
Dosage schedule for cats
The recommended minimum doses are 10 mg/kg bodyweight imidacloprid and 1.0
mg/kg bodyweight moxidectin, equivalent to 0.1 ml/kg bodyweight of the veterinary
medicinal product.
Underdosing could result in ineffective use and may favour resistance development.
To ensure a correct dosage, body weight should be determined as accurately as
possible. For infestations/infections with the indicated parasites, the need for and
frequency of re-treatment(s) should be based on professional advice and should take
into account the local epidemiological situation and the animal’s lifestyle.
Weight of
cat [kg]
Pipette size to be
used
Volume
[ml]
Imidacloprid
[mg/kg bw]
Moxidectin
[mg/kg bw]
> 4–8 kgRidamax for large cats0.810–201–2
Flea treatment and prevention (Ctenocephalides felis)
One treatment prevents future flea infestation for 4 weeks. Existing pupae in the
environment may emerge for 6 weeks or longer after treatment is initiated, depending
upon climatic conditions. Therefore, it may be necessary to combine animal
treatment with environmental treatments aimed at breaking the flea life cycle in the
surroundings. This can result in a more rapid reduction in the household flea
population. The veterinary medicinal product should be administered at monthly
intervals when used as part of a treatment strategy for flea allergy dermatitis.
Treatment of ear mite infestation (Otodectes cynotis)
A single dose of the veterinary medicinal product should be administered. A further
veterinary examination 30 days after treatment is recommended as some animals
may require a second treatment. Do not apply directly to the ear canal.
Treatment of notoedric mange (Notoedres cati)
A single dose of the veterinary medicinal product should be administered.
Treatment of the lungworm Eucoleus aerophilus (syn. Capillaria aerophila) (adults)
A single dose of the veterinary medicinal product should be administered.
Prevention of Aelurostrongylus abstrusus
The veterinary medicinal product should be administered monthly.
Treatment of Aelurostrongylus abstrusus
The veterinary medicinal product should be administered monthly for three
consecutive months.
Treatment of the eye worm Thelazia callipaeda (adults)
A single dose of the veterinary medicinal product should be administered.
Heartworm prevention (Dirofilaria immitis)
Issued: January 2024
AN: 01889/2022
Cats in areas endemic for heartworm, or those which have travelled to endemic
areas, may be infected with adult heartworms. Therefore prior to treatment with the
veterinary medicinal product, the advice provided in section 4.5 should be
considered.
For prevention of heartworm disease, the veterinary medicinal product must be
applied at regular monthly intervals during the time of the year when mosquitoes (the
intermediate hosts which carry and transmit heartworm larvae) are present. The
veterinary medicinal product may be administered throughout the year. The first dose
may be given after first possible exposure to mosquitoes, but not more than one
month after this exposure. Treatment should continue at regular monthly intervals
until 1 month after the last exposure to mosquitoes. To establish a treatment routine,
it is recommended that the same day or date be used ea
[Text truncated]
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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