Westie puppy itchy skin & food trial advice

A 5-month-old Westie with itchy skin and paw chewing, and a vet already suggesting a food trial — you're in exactly the right place, and honestly you're ahead of most people who just wait and hope it resolves. Westies are genuinely one of the breeds most prone to skin issues, and food is a very real trigger, so your vet is thinking correctly. To point you toward the right food, can I ask: what are they currently eating, and do you know if they've been on that food since you got them, or did they come from the breeder on something different?

That's really useful — and it actually gives us a clear direction. Royal Canin's breed-specific range uses chicken and chicken by-products as the main protein, along with wheat and corn, so she's had consistent exposure to all of those since 8 weeks. For a food trial to be meaningful, you ideally want a single novel protein she hasn't encountered before, with a very clean ingredient list — no grains, no added flavourings, minimal fillers. Has she had any other foods, treats, or chews, even occasionally? I want to make sure we pick a protein that's genuinely new to her.

Perfect — stopping the treats is exactly right, they're notorious for derailing food trials. Given she's been on chicken, wheat, and corn consistently, my recommendation is Canagan Grain Free Scottish Salmon for Puppies. Salmon is a genuinely novel protein for her, it's grain-free so you're removing wheat and corn from the picture entirely, and Canagan uses a very short, clean ingredient list — no artificial anything, no fillers. Crucially, it's also nutritionally complete for puppies, which matters at 5 months when she's still developing. It's widely available on Amazon UK. A proper food trial needs 8–12 weeks of strict adherence — same food, no treats, no extras — so commit to the timeline your vet suggested. If the itching improves, that points clearly to a dietary trigger. If it doesn't shift at all, at least you've ruled food out and can look at environmental causes with your vet.

Normally I'd say a slow 7-day transition mixing old and new food, but with a food trial the guidance is slightly different — some vets prefer a clean switch straight to the new food so you're not prolonging exposure to the suspected trigger. Worth a quick call to your vet to confirm their preference. If they're happy with a gradual switch, do it over 7–10 days: roughly 25% new food for the first few days, 50% by the middle of the week, 75% by day 8, and fully switched by day 10. Some loose stools for a day or two in transition is normal and not a sign the food is wrong — it's just the gut adjusting.

It takes a while — genuinely. Skin takes longer to respond than the gut does. Most vets say you need 8–12 weeks minimum to see a meaningful change in skin and coat symptoms, and some dogs take a little longer. Don't be disheartened if weeks 2–4 look the same as before. What you're watching for is a gradual reduction in scratching frequency and intensity, and less paw chewing over time — not a sudden overnight fix. Keep a simple note on your phone each week rating her itchiness on a rough scale of 1–10. It makes it much easier to see progress that your eye might miss day-to-day, and it's useful information for your vet at the follow-up.