Activyl Spot-on for Dogs & Cats

Activyl Spot-on for Dogs & Cats

  • Cat » Small » 4 Pipettes £16.99
  • Dog » Large » 4 Pipettes £25.99
  • Dog » Medium » 4 Pipettes £22.49
  • Dog » Small » 4 Pipettes £19.99
  • Dog » Toy » 4 Pipettes £19.99

Selection of 5 products from

£16.99 to £25.99


Activyl Spot-on is the latest flea treatment for dogs and cats made by MSD. Fleas have shown no resistance to this innovative product which has a totally unique active ingredient, called indoxacarb. Activyl is supplied in pipettes of two different sizes for cats and five different sizes for dogs, so that each animal receives just the right dose for its bodyweight. One pipette is used per month to maintain effective flea control on puppies and kittens from 8 weeks of age..

Activyl is the first product designed to achieve flea control through the use of "metabolic activation, or bioactivation". It is applied once every month to the surface of the skin where fleas take it up and they then convert it into a highly active metabolite. The drug in Activyl has very little effect without the activation until it is taken in by a flea or other insect, so the possibility of toxicity to the base ingredient is very slim. Mammals are not able to activate the compound in this way and so are not exposed to the active insecticide by licking at their coat or swallowing hair - unlike other spot-on treatments.

Qualitative and quantitative composition

Each ml contains 195 mg indoxacarb.

Each unit dose pipette delivers:

Unit dose (ml)

Indoxacarb (mg)

Activyl spot-on solution for very small dogs



Activyl spot-on solution for small dogs



Activyl spot-on solution for medium dogs



Activyl spot-on solution for large dogs



Activyl spot-on solution for extra large dogs



Activyl spot-on solution for small cats



Activyl spot-on solution for large cats



Excipients: Isopropyl alcohol 354 mg/ml.

For a full list of excipients, see Section "Pharmaceutical Particulars".

Pharmaceutical form

Spot-on solution. A clear, colourless to yellow solution.

Clinical particulars

Target species

Dogs and cats

Indications for use

For dogs and cats: Treatment and prevention of flea infestation (Ctenocephalides felis).The veterinary medicinal product can be used as part of a treatment strategy for flea allergy dermatitis (FAD). Developing stages of fleas in the pet’s immediate surroundings are killed following contact with Activyl treated pets.



Special warnings for each target species

The safety of Activyl has not been established in dogs and cats younger than 8 weeks of age.

The safety of Activyl has not been established in dogs weighing less than 1.5 kg and in cats weighing less than 0.6 kg.

Special precautions for use

Care should be taken to apply the dose to an area where the animal cannot lick it off, as described under Amounts to be administered and administration route, and to ensure that animals do not groom each other immediately following treatment. Care should be taken to ensure that the content of the pipette or the applied dose does not come into contact with the eyes of the recipient and/or other animals. The product remains effective following shampoo treatment, water immersion (swimming, bathing) and exposure to sunlight. However, animals should not be allowed to swim or treated with shampoo within 48 hours after treatment.

User warnings:

Do not eat, drink or smoke while handling the veterinary medicinal product. The sachet is child-resistant. Keep the product in the sachet until use, in order to prevent children from getting direct access to the product. Keep the used pipette out of reach and sight of children. Wash hands immediately after use. This product contains indoxacarb. People with known hypersensitivity to indoxacarb should not use this product. As the veterinary medicinal product may cause moderate eye irritation, avoid contact with eyes. If this occurs, rinse slowly and gently with water. This product is highly flammable. Keep away from heat, sparks, open flame or other sources of ignition.

Adverse reactions

A brief period of hypersalivation 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.Transitory scratching or hair loss at the application site may occur.These effects will usually resolve without treatment.

The application of the veterinary medicinal product may produce a local, temporary oily appearance or hair clumping at the application site. A dry white residue may be also observed. This is normal and will generally resolve within a couple of days after administration. These changes do not affect the safety or efficacy of the veterinary product.

Use during pregnancy, lactation or lay

Do not use in pregnant or lactating animals or in animals intended for breeding.


None known.

Amounts to be administered and administration route

Dosage schedule:

Dogs: The recommended dose is 15 mg indoxacarb/kg bodyweight, equivalent to 0.077 ml/kg bodyweight. The following table defines the size of pipette to be used according to the weight of the dog:

Weight of Dog (kg)

Pipette size to be used

Volume (ml)

Indoxacarb (mg/kg)

< 6.5

Activyl Spot-on-Solution for very small dogs


Min. of 15

6.6 - 10

Activyl Spot-on solution for small dogs



10.1 - 20

Activyl Spot-on solution for medium dogs



20.1 - 40

Activyl Spot-on solution for large dogs



40.1 - 60

Activyl Spot-on solution for very large dogs



> 60 kg

The appropriate combination of pipettes should be used.

Cats: The recommended dose is 25 mg indoxacarb/kg bodyweight, equivalent to 0.128 ml/kg bodyweight. The following table defines the size of pipette to be used according to the weight of the cat:

Weight of Cat (kg)

Pipette size to be used

Volume (ml)

Indoxacarb (mg/kg)

≤ 4

Activyl Spot-on solution for small cats


Minimum of 25

> 4

Activyl Spot-on solution for large cats


Maximum of 50

Method of administration: For spot-on use only. Open one sachet and remove the pipette.

Step 1: The animal should be standing for easy application. With one hand, hold pipette in an upright position away from your face and with the other hand, snap tip open by bending it and folding it back on itself.

Step 1

Activyl figure 1 (MSD)

Step 2: Part the hair until the skin is visible and place pipette tip against the skin between the shoulder blades for dogs, or at the base of the skull for cats. Squeeze pipette firmly applying the entire contents directly to the skin.

Step 2

Activyl figure 2 (MSD)

In larger dogs, the entire contents of the pipette(s) should be applied evenly to two or three or four spots, all located at different application sites along the backline from the shoulder to the base of the tail. Do not apply an excessive amount of solution at any one spot which could cause some of the solution to run off the side of the animal.

Step 3

Activyl figure 3 (MSD)

Treatment schedule: Following a single administration, the veterinary medicinal product will prevent further flea infestation for at least 4 weeks.


No adverse effects were observed in dogs and cats aged 8 weeks or older administered 5 times the recommended dose on 8 occasions at 4 weeks intervals or administered 5 times the recommended dose on 6 occasions at 2 weeks intervals.

Withdrawal periods

Not applicable.

Pharmacological particulars

Pharmacodynamic properties

ATC Vet Code QP53AX27

Pharmacotherapeutic group Pharmacotherapeutic group: Ectoparasiticides for topical use.

Indoxacarb is an ectoparasiticide belonging to the oxadiazine chemical family. After being converted into a metabolite, indoxacarb is active against adult, larval and egg stages of insects. In fleas, in addition to its adulticidal activity, indoxacarb activity on the developing larval stages in the immediate surroundings of the treated pet has been demonstrated. Indoxacarb is a pro-drug that requires bioactivation by the insect enzymes to exert its pharmacodynamic effects. It enters the insect primarily through ingestion but is also absorbed, to a lesser degree, through the insect cuticle. In the mid-gut of susceptible insect species, the insect’s enzymes remove the carbomethoxy group from parent indoxacarb, and convert it into its biologically active form.The bioactivated metabolite acts as a voltage-dependent sodium channel antagonist in insects, by blocking the sodium channels that regulate the flow of sodium ions in the insect’s nervous system. This results in a rapid cessation of feeding within 0 to 4 hours after treatment followed by cessation of egg laying (oviposition), paralysis and death occurring within 4 to 48 hours.

Pharmacokinetic properties

Following a single spot-on application of the product, indoxacarb can still be detected in both skin and hair coat after 4 weeks post-treatment. Absorption through the skin also occurs, but this systemic absorption is partial and not relevant for the clinical efficacy. The absorbed indoxacarb is extensively metabolised by the liver to a variety of metabolites. The major route of excretion is in faeces.

Pharmaceutical particulars


Triacetin, Ethyl acetoacetate and Isopropyl alcohol.

Major incompatibilities

None known.

Shelf life

Shelf-life of the veterinary medicinal product as packaged for sale: 3 years.

Special precautions for storage

This veterinary medicinal product does not require any special temperature storage conditions. Store in the original package, in order to protect from moisture.

Immediate packaging

Cardboard box of 1 or 4 spot-on applicators, consisting of 0.51, 0.77, 1.03, 1.54, 3.08 and 4.62 ml pipettes. One size only per box. The pipette consists of a blister film (polypropylene/cyclic-olefin-copolymer/polypropylene) and a foil lidstock (aluminium/polypropylene co-extruded) sealed into aluminium sachets. Not all pack sizes may be marketed.

Not all pack sizes may be marketed.


Any unused veterinary medicinal product or waste materials derived from such veterinary medicinal products should be disposed of in accordance with local requirements. Activyl should not be allowed to enter surface waters as indoxacarb may have harmful effects on aquatic organisms.

Marketing Authorisation Holder (if different from distributor)

Intervet International BV, Wim de Körverstraat 35 , 5831 AN Boxmeer, The Netherlands.

Marketing authorisation number

Activyl 100 mg spot-on solution for very small dogs


Activyl 100 mg spot-on solution for small dogs


Activyl 100 mg spot-on solution for medium dogs


Activyl 100 mg spot-on solution for large dogs


Activyl 100 mg spot-on solution for extra large dogs


Activyl 100 mg spot-on solution for small cats


Activyl 100 mg spot-on solution for large cats


Date of the first authorisation or date of renewal

18 February 2011.

Date of revision of the text

March 2012.

Any other information


Legal category


Need help or advice? Contact us:

  • Landline: 01582 842096
  • Mon - Fri: 8:30am - 5:00pm
  • Sat: 9:00am - 1:00pm
  • Email: [email protected]

All prices include VAT where applicable.

Delivery Information

How quickly do you deliver?

Under almost all products on our website is an Estimated dispatch time, check this for a delivery prediction specific to the item you are looking to purchase. These badges are updated live based on the stock levels we have and also those of our suppliers - so are usually very accurate, but cannot be guaranteed. In more general terms, we aim to dispatch all orders within 1 working day of receiving payment (and a prescription if required). If we cannot do so within 3 working days we will contact you by email.

What do you charge for delivery?

For UK delivery, we charge the following:

Order Total Weight Delivery
£0-£28.99 Under 2kg £2.99
2kg+ £4.99
£29-£38.99 Under 2kg Free
2kg+ £4.99
£39+ Under 2kg Free
2kg+ Free

Prices quoted are for delivery to all parts of mainland UK except certain Scottish postcodes (where the price is higher for items sent by courier. Delivery of food abroad (including Channel Islands, N. Ireland and other islands around the UK) is charged at a higher price and free delivery is not available. Temperature controlled products, such as Insulin, are also not always subject to the standard and/or free delivery options.

For full information on our delivery charges, including prices on heavy deliveries to Scotland and abroad, see our delivery information page.

We can deliver most items to all around the world, but prices do vary. The majority of light weight orders (less than 1.5kg) can be delivered for a flat rate of £10. For an accurate estimate of the delivery charge, please put the items you require in your basket and use the "Estimate Delivery" system on the shopping basket page (you only need to enter your country and postal/zip code) for a quick quote. For deliveries to the USA you may need to go to the checkout page and enter your full address to get a quote (as some services need your state in order to quote too). For more information on international deliveries, please see our delivery information page.

Delivery of aerosols

Due to air freight restrictions aerosols cannot ever be sent abroad by Royal Mail. We appreciate your understanding.

Delivery of temperature controlled items

Some products, such as insulin and frozen food, need to be delivered in insulated packaging to prevent them from getting too warm (or too cold) during transit from us to you. Purchasing any of these items in your order will result in a £1.99 charge being added to the total to cover the high cost of the insulated packaging materials. You only pay the £1.99 once per order, regardless of how many temperature controlled items you purchase in that order.

How do I cancel or return an order?

Please call us as soon as possible if you need to amend or cancel an order on 01582 842096. If your order has been processed for dispatch we will be unable to cancel or amend the order. You will however be able to return your product for a full refund*.

To return an item, you must contact us by phone or email to arrange this BEFORE posting any product back to us. We will explain the process at this stage for you.

*For full details on returns, see our terms and conditions page.


Q & A

Below are some recent questions we've received regarding Activyl Spot-on for Dogs & Cats, including answers from our team.

8 September 2014 9:42am



I was given this on saturday 6th sept put on my cat.
How long does it take to kill all fleas?

  • Non-Executive Director

In the early autumn of a year like we have had, it can take a long time! This is because new fleas will be hatching out in the environment where your cat (and other animals) have been going for the last few months. Waves of new fleas might well be landing on your cat every day. They will die off quite soon (a day or so usually if you applied the treatment effectively) but more fleas will appear. I would suggest you treat the house with product like Indorex after carefully vacuuming all the carpets and furnishings. You will get rid of all the fleas in time, but it is rarely an instant result. It depends on how effective your treatments have been over the last few months and so what size the background flea population is.