Flea treatment for Westies with greasy skin

A Westie with greasy skin and spot-on residue is a really common frustration — that oily coat type means topical treatments often don't absorb properly, they sit on the surface, leave a greasy patch, and frankly the efficacy suffers too. The good news is there's a cleaner solution. Before I point you in the right direction — is your Westie mostly outdoors, do you walk in woodland or fields, and has a vet diagnosed the greasy skin as something specific like Malassezia or seborrhoea?

That's exactly the profile where I'd steer clear of spot-ons entirely. With seborrhoeic skin the coat barrier is already compromised, and spot-ons rely on distributing through the skin's natural oils — if those oils are dysregulated, absorption is unpredictable. For a dog your size, in a tick-risk area, I'd go straight to NexGard (afoxolaner) — it's an oral chew, beef-flavoured, given monthly. It covers both fleas and ticks including Ixodes (the main UK Lyme disease carrier), and because it's systemic there's zero interaction with her skin condition. No residue, no patchy absorption, no greasy neck. It's prescription-only in the UK, so your vet needs to prescribe it, but most will do so readily for a dog already under their care.

Reasonable concern. NexGard is an isoxazoline — the same class as Bravecto and Simparica — and there is a black box warning from regulators that in rare cases these can trigger neurological side effects, particularly in dogs with a history of seizures. Westies aren't a breed with a particularly elevated seizure risk, and at 8 years old with no history of neurological issues she'd be considered low-risk. Millions of dogs take it without incident. That said, because she's a senior, it's worth your vet running a quick check on liver and kidney function before starting any new systemic treatment — not because NexGard specifically demands it, but just good practice at her age. Has she had any bloodwork recently?

If you need something while you're waiting for the vet appointment, a Seresto collar is an option — it's low-residue compared to spot-ons and repels as well as kills. But honestly, given her skin condition and the tick exposure, I'd push for the NexGard prescription sooner rather than later. If your vet suggests Bravecto instead (it's the same class, just dosed every 12 weeks rather than monthly), that's a perfectly reasonable alternative — same efficacy, just less frequent dosing. Either way, avoid anything that goes on the skin. The oral route is the right call here.

Good plan. When you go, mention specifically that previous spot-ons have left residue and you'd like to discuss an oral isoxazoline — that'll save time. And if you want a tick check routine while you're sorting the prescription, a fine-toothed tick comb through her coat after every walk is worthwhile. Westies' dense double coats are good at hiding ticks, especially around the ears and between the toes.