Flea prevention for indoor cat with new dog

A rescue dog joining the household is genuinely one of the most common ways a strictly indoor cat ends up with fleas — so you're right to think ahead. Before I point you to anything, I want to flag the single most important safety rule in cat flea treatment: permethrin and several other insecticides that are completely safe for dogs are toxic to cats, sometimes fatally so. Never use a dog flea product on your cat, and be careful with any dog spot-on around your cat until it's fully dry. Now — how old and how heavy is your Himalayan, is this purely prevention or do you have fleas already, and have you treated your home at all?

Good, you have a clear window to get ahead of this. Before I nail down the recommendation, can you tell me roughly how big the dog is and what flea treatment the rescue centre is sending him home with, if you know? That affects what's safe to use in a shared space.

Perfect, that's really helpful. For your Himalayan, I'd go with Bravecto Spot-On for Cats (2–6.25kg pack covers her weight exactly). It's a single application that lasts three months, so you apply it before the dog arrives and you're protected through the entire settling-in period without needing to remember monthly doses. It's prescription-only, which means you'll buy it through an online vet pharmacy like PetDrugs Online or VetUK — straightforward process, no appointment needed, just answer a few questions about your cat. For the dog, use a separate permethrin-free spot-on like Bravecto Spot-On for Dogs or a Seresto collar — crucially, keep them apart for 24 hours after any dog spot-on application until it's absorbed, just as a precaution. One more thing worth doing: a single can of Indorex Defence household spray on your soft furnishings and carpets before the dog arrives. It kills flea eggs and larvae for up to 12 months and means you're not just treating animals while a home reservoir builds up.

It's a fair thing to check. Bravecto for cats uses fluralaner, which is in a completely different chemical class from permethrin — it's not the same family that causes feline toxicity. It's been through full EMA veterinary approval and has a strong safety record at the licensed dose. The alarming posts you'll see online tend to conflate different products, or involve off-label use, or are simply anecdotal without a confirmed link. That said, if your cat has a history of neurological conditions or seizures, mention that when you fill in the online vet form — they'll flag it if there's any reason to choose something else for her specifically.

You're well set up. Apply the Bravecto a day or two before the dog arrives so it's fully absorbed and working, spray the Indorex on carpets and soft furniture the same day with the windows open, and you've covered every angle. Good luck with the new arrival — the cat may have opinions about him for a while, but at least fleas won't be one of the complications.