Fleas are a type of external parasite. There are different species of fleas, such as dog fleas, cat fleas, rabbit fleas and even human fleas. However it is possible for many species of fleas to infest more than one host species.

For example, the most common species of flea in the UK is the Cat flea (Ctenocephalides felis). They are extremely common whose primary host is domestic cats. But they are known for readily biting humans and dogs too. Trust me, I know; when I have a patient in with fleas, I regularly go home with flea bites – they are very itchy!

Prevention is better than cure

Of course, from an animal health and welfare perspective I recommend that prevention is better than cure. And this definitely applies to fleas.

Mostly, fleas are just a small annoyance if caught. But you have to treat them for a minimum of three months to break the life cycle and prevent reinfection. You have to treat the house, too, because a large percentage of the population does NOT live on the animal; 95% of the flea population, made up of eggs, larvae and pupae, is found in the environment. And you have to ensure your animals do not get any more serious issues, such as flea allergic dermatitis (FAD).

What is FAD?

Flea-allergic dermatitis (FAD) is an allergy to flea saliva. If your cat has FAD, it may experience intense itching and a rash each time they are bitten by a flea.

The rash is typically small and bumpy and often tends to develop around their head, neck, tummy, and back legs. The cats may scratch these areas causing self-trauma and may also over groom causing alopecia (loss of hair).

How often should I treat?

While flea infestations peak in summer and autumn, the European Scientific Counsel for Companion Animal Parasites (ESCCAP) UK and Ireland state, in their guidelines for the control of ectoparasites in dogs and cats, that flea infestation can occur throughout the year. And that year-round flea control is sometimes necessary and remains important to minimise the risks of UK household infestations.

What can I use to prevent fleas?

There are different types of flea treatment available:

Prescription flea treatments

Prescription medications are proven and effective products licensed for an animal, to treat or prevent a certain issue, and they can only be prescribed by a vet.

If your cat is healthy and visits your vet regularly, your surgery may be happy to dispense prescription flea products without an appointment. To be given prescription medicine, animals are required to be under a vet’s car. So if they haven’t been examined for a while you will currently need to book an appointment for them to be checked.

The positives of prescription products are that they are batch tested, effective, and given alongside guidance for your individual pet. Fleas are not normally the only parasite you need to treat for. And looking into your individual pets ‘risks’ for other parasites such as tapeworm can help guide a more tailored parasite plan for you.

All veterinary medicines are subject to rigorous pharmacovigilance reporting (practice of monitoring the effects of medical drugs after they have been licensed for use) and follow-up requirements. This means suspected lack of efficacy (which could be due to resistance or other factors such as incorrect administration) would be investigated and reported to the regulatory authorities. This is positive as we know that efficacy (ability to produce a desired or intended result) is monitored closely. 

Non-prescription flea treatments

‘Off the shelf’ treatments (Authorised Veterinary Medicine – General Sales List) are non-prescription products that can be bought without a prescription and are on general display in supermarkets and pet shops.

They tend to contain potentially less effective ingredients than prescription and NFA-VPS products. 

AVM-GSL – Authorised Veterinary Medicine, General Sales List are the least heavily regulated medicines. This is because, in general, they have the least capacity to cause harm. And they may be sold by anyone so are easily accessible. You can often find them in supermarkets which is great for accessibility. But you need to be aware that they are often the least effective drugs on the market. And they may not work to quickly and effectively kill the fleas on your pet or prevent them in the first place.

They’re also only safer if used in the species they’re designed for. Many non-prescription dog flea treatments contain permethrin and are fatal to cats!

What are NFA-VPS products?

‘NFA-VPS’ treatments are treatments that can be bought without a prescription. But they are only available from locked cupboards in pharmacies, vet clinics and pet shops. NFA-VPS products tend to be more effective than ‘off the shelf’ products, and the pharmacist or SQP supplying them will typically ask more in-depth questions about your pet, for example you will need to know your cat’s weight to buy some. 

Benefits of prescription only

Before being placed on the market, all veterinary medicines undergo a detailed regulatory assessment by independent regulators, who consider the balance of the benefits provided from using the product, compared with the potential risks. This is true of all drugs – but the data can be difficult to interpret if you’re not an animal health professional.

This includes looking at:

  • Benefit/risk assessment considering the product’s safety (including environmental safety)
  • Quality and efficacy
  • Determination of the product’s legal supply classification (who can prescribe/supply) 
  • Any warnings to be placed on the packaging or restrictions that should be placed on the product’s use

Non-prescription products usually contain older ingredients, sometimes even licensed under “grandfather rights”. This means that they have been used for so long (even before the current licensing regime came into effect) that they can continue to be used. More importantly, non-prescription products usually contain less effective active ingredients: this is why they have been authorised for sale under a lower level of professional supervision. 

The benefits of getting prescription only treatments are that you know they are licensed for use so have evidence to back up their claims, they usually have up-to-date information to tell you how quickly they will kill the fleas, how long or if they can repel them, if they have any impact of the environmental burden too, how long they will last, and how their efficiency reduces over time. For example, some treatments can tell us that they are 95+% effective and this may drop to around 80% after a number of weeks or months, which is when reapplication is suggested.

This kind of information is really useful, alongside the support and guidance of your veterinary team and the fact we know these products are tested in modern conditions, and regulated to a high-quality, means that this is the type of treatment I would use for my own pet – and the type I would generally suggest to my clients as well.

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