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Why can I still see fleas on my pet after I’ve applied FRONTLINE Spot On?

Seeing fleas soon after applying the product is a sign that the product is working. FRONTLINE Spot On kills fleas by overstimulating their nervous systems, so disorientated hyperexcited fleas can rise to the surface of the pet’s coat and become more visible.


Also, it’s important to know that it’s normal to see fleas on your pet as they pick up new fleas that are hatching out from pupae in the environment. These will be killed within 24 hours of jumping onto your treated pet.


However, if you’re seeing a large number of fleas, this is a sign that your home environment is infested. Large numbers of fleas could be hatching out of flea eggs in the environment. Even if you have treated your home with an Insect Growth Regulator (IGR) spray this will not kill the pupae. An IGR only kills eggs and larvae, so new adult fleas will still be seen on your pet until they have all hatched out of their pupae and into the environment. You should treat your pet every four weeks to bring the flea population under control.


More advice on treating an infestation

Can I apply FRONTLINE Spot On anywhere on my pet?

No. You must apply it directly onto the pet’s skin, not on their hair, at the base of the neck between the shoulder blades, where your pet cannot lick it off.

Can my pet be bathed or go swimming after I’ve applied FRONTLINE Spot On?

Yes, they can from 48 hours after application. FRONTLINE Spot On is water resistant and will remain effective even if your pet gets wet. If your pet goes swimming or is bathed more than once a week, we recommend you apply FRONTLINE Spot On every four weeks.

Do I need to treat my pet for fleas even in colder months?

Yes. With centrally heated homes, fleas can be a problem all year round.

I live in a highly tick-infested area. How often do I need to treat my pets?

Every four weeks. Ticks have been found to be active even in cold winter months, so you should treat all year round. Remember FRONTLINE Spot On is not a tick repellent so you may still see some ticks on your pet. They should be killed within 48 hours.

There are other flea treatment products which contain fipronil. Are these products the same as FRONTLINE Spot On?

No, check the label claims. Although they contain the same ingredient there are differences.

FRONTLINE® Spot On contains fipronil NFA-VPS (UK); POM (Ireland). FRONTLINE Combo® contains fipronil and (S)-methoprene POM-V (UK);
POM (Ireland). ®Registered Trademark. For further information contact Merial Animal Health Ltd, CM19 5TG, UK. ©Merial Ltd 2013. All rights reserved.