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Dr. B.
Dr. B., Board Certified Veterinarian
Category: Vet
Satisfied Customers: 22584
Experience:  General practice veterinary surgeon with extensive experience in a wide range of species.
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Hi! I used Frontline on my 2 dogs 5 days ago but they still

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I used Frontline on my 2 dogs 5 days ago but they still seem to be scratching just as much. Then I noticed that the date on the pack was 2009. Does that mean it had gone off and I need to get a new supply? And can I use it immediately or should I wait until the month is over before applying new Frontline?
Thanking you in anticipation
Frances Mulvey

Hello & welcome, Frances. I am Dr. B, a licensed veterinarian and I would like to help you with your wee ones today.

Now it is possible that the out of date Frontline has lost some potency and therefore isn't tackling the fleas as it usually will. Therefore, if you are still seeing fleas or flea dirt in their coat, then you can consider retreating after a week has passed since the last dose (to avoid any risk of adverse effects from double treating).

Otherwise, if you aren't actually see those creepy crawlies and their waste products, then we have to consider that the lads may be still itching a bit due to the allergic effects of flea saliva being inoculated into their skin from the fleas' bites. In that case, we can counteract that allergic reaction by treating with short course of Piriton available over the counter from the chemist. Usually we will just need to treat for a week (using 2mg or half tablet for small dogs and a 4mg or one whole tablet for larger dogs). This can be given twice daily, though as antihistamines can make dogs a wee bit drowsy (as it can with people) so once daily is fine too.

So, it is likely that the out of date Frontline has lost some of its potency thus not addressing the fleas like before. So, if you are still seeing fleas, give them another 2 days and reapply with a fresh treatment. Otherwise, if there are no fleas in sight, a short course of Piriton may be all they need to settle the allergic itching from those flea bites.

I hope this information is helpful.

If you need any additional information, do not hesitate to ask!

All the best,

Dr. B.


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