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Flea control

Fleas are the most common parasite in household pets and every cat and dog is likely to be infected at some stage in its life. However, with the advent of modern products it is possible to prevent fleas from becoming a problem in your home. Working closely with your vet, who will give you advice on how to use these products effectively, you will be able to stop these nasty little insects making a meal of your pet and you!

Your questions answered

Why do I need to treat my pets for fleas?

Fleas can be a real menace in centrally heated homes, particularly if you have more than one pet. They are the most common cause of skin disease in cats and dogs (causing allergies as well as irritation) and may also carry other diseases. Unfortunately fleas are not too particular and will happily bite you and your family if they can't find a convenient pet!

How can fleas be controlled?

To ensure your home is free from fleas you must control them on your pets and in the environment.  There are many products available to kill adult fleas on pets. These vary in their formulation, speed, efficacy, duration of action, ease of use and cost. If your pet is allergic to fleas it is very important to prevent any flea bites, so you should use a product which kills fleas rapidly.

Products for controlling fleas act in 1 of 3 ways:

  1. Chemicals which are toxic to the adult flea - These products are usually applied to the animal's coat and poison any flea that passes through. Some chemicals can also be applied to the house so that fleas can be killed whilst they are away from the pet.
  2. Hormones which make the adult female fleas sterile - These are hormones that can enter your pet's blood stream and whilst they have no effect on the pet, when a female flea bites and drinks the blood the hormone effectively sterilises her, so that any eggs she lays will not hatch. This can be a good way to prevent fleas from coming back but since adult fleas are not killed you may need to use another product in the meantime to remove them from your pet.
  3. Chemicals which prevent development of immature fleas - These can be applied to the environment and act as a growth regulator preventing the immature fleas developing into adults.

How can these treatments be given?

Some products kill adult fleas and are available as a pump or spot-on treatment that is applied to your pet's coat (topical). In some cases these can be used on animals as young as two days old.

Other products contain a chemical that prevents the flea eggs from hatching.
These can be given to the dog as a liquid once a month or by injection every six months (systemic). However it is important to remember that these treatments do not kill adult fleas.

There are also products that can be used to treat the environment. Sprays
contain substances that prevent development of the flea's hard coat and
these stop larvae developing into adults.

Chemicals which mimic juvenile hormones such as methoprene and pyriproxifen
also prevent flea larvae developing into adults. A single application of
these sprays to the environment can last for six months to a year, depending
on the product used. These products also kill flea eggs.

How often do I need to treat my pet?

Fleas can breed and cause problems all year round in centrally heated homes. Regular treatment with the products recommended by your vet should keep fleas under control. The interval between treatments will depend on your particular circumstances and the products that you use. In most cases you will need to treat your pet's coat at least every 3 months (and with some products as often as once a week). Some products are given monthly by mouth. The key to success of whichever product you choose is to use it regularly according to the manufacturers guide.

Do flea collars work?

The collars containing insecticides to control fleas are not very effective. Very quickly they only affect fleas very close to the collar and by the time a flea gets there it may already have bitten your pet elsewhere. In addition the collars themselves can cause an allergic reaction in some pets and cats may get caught up by a collar and strangled.

The ultrasonic flea collars probably do not work.

What if I can't spray my pet for fleas?

The chemicals used to kill fleas are produced in all sorts of formulations. You will usually be able to find a product to suit your needs. If you are really unable to treat your pet by yourself you may need to get someone to help you hold your pet. This may be a friend or a professional (dog groomer, or veterinary nurse).

Some products can be given my mouth (tablet for dogs or liquid placed on food for cats) or injection and you may find it easier to treat your pet in this way.

Why do I need to treat the house?

Only the adult forms of the flea live on your pet. The immature forms (larvae) are tiny maggot-like creatures that live in carpets and your pet's bedding. If you are going to tackle fleas you must address this pool of developing parasites that are ready to leap back onto your pet as soon as you remove the resident adult fleas. It is important to treat the areas where your pet spends most of its time - particularly the places where it sleeps. Washing your pet's bedding in hot water will destroy the young fleas (but not the eggs) and vacuuming your carpets also helps keep the numbers down. Vacuum bags should be disposed of to prevent collected immature flea stages continuing to develop in the house. Cleaning carpets with a steam cleaner should kill some of the larval fleas, and also remove the bits of organic matter that accumulate in carpets that the larvae feed on. Anything that is heavily infested, such as pet bedding, should be disposed of. However in most cases you will need to use a chemical to kill the immature fleas as well as the adults.

How do I get rid of fleas in the house?

Insecticide spray treatments can be used on carpets to reduce numbers of fleas.  Some products target the adult flea whilst others are growth regulators that prevent eggs from hatching and the larval fleas from turning into adults that can re-infect your pet.

You must never apply a product designed for use in the environment directly to an animal. However there are some products that you can apply to your pet that will also have an effect on fleas where your pet spends a lot of time.

Your vet can advise you on which product, or combination of products, to use. You must continue to treat your pet and your home all year round, even if you do not see fleas.

How do I stop fleas coming back?

Unless you remove all the immature fleas from your house they will keep getting back you're your pet. There are a number of ways of preventing your pet being re-infested with fleas.

Long acting products can be used to kill all the flea stages in the house. In order to do this effectively the whole house must be treated which is expensive and difficult as immature fleas often live in hard to reach places. Many people find that they prefer to use something that prevent the immature forms from developing into adult fleas. If you can break the flea's lifecycle and adults are not produced they will not be able to reproduce. There are number of products that will do this but they must be given to all cats and dogs in the household. These products do not affect adult fleas. Alternatively a long acting treatment that kills adults on the infested animal can be used on all animals in the household which will prevent egg laying and thereby break the cycle.

How safe are flea control products?

Most products are very safe if used strictly according to the manufacturers instructions. Always follow these simple rules:

  • Read the instructions carefully before using the product.
  • Never treat a cat with a product designed for use in a dog (unless instructed by your vet). Cats are particularly susceptible to developing toxic reactions to flea control products containing traditional insecticides.
  • Never treat an animal directly with a product designed for use in the environment.
  • Do not apply the product more often than recommended by the manufacturer.
  • If treating a young animal ensure the product is safe for that age.
  • Do not combine products (unless instructed to do so by your vet).
  • Where possible treat animals in a well-ventilated area and after treating the house air well before accessing again.

Some animals can also be sensitive to other chemicals in the flea control product.

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