Switching dog probiotic brands smoothly

Switching probiotic brands is one of the more straightforward supplement changes you can make — the gut doesn't tend to rebel the way it does when you swap actual food. That said, a 6-year-old Weimaraner is a good candidate for a consistent probiotic if there's a reason behind it. What's prompting the switch — was the old brand not delivering results, a stock issue, or just looking for better value? And is there anything specific you've been trying to address, like loose stools, post-antibiotic recovery, or general digestive sensitivity?

That's a sensible position — if his gut is settled and you're happy with the results, the goal is finding something equivalent, not experimenting. Pro-Kolin's main active is Enterococcus faecium at a decent CFU count, plus some kaolin for stool firming. You don't need to replicate it exactly, but you do want a product with a reliable CFU count and a strain that's well-studied in dogs. Can I ask what format you've been using — the paste, the powder, or the capsules? And roughly what you're paying at the moment?

Good — powder format makes switching easy since there's no palatability issue to worry about with a Weimaraner, who will almost certainly eat anything. For a direct switch that won't rock the boat, I'd go with Purina Pro Plan Veterinary Diets FortiFlora. It's a single-strain powder — Enterococcus faecium SF68, the most researched probiotic strain in dogs — and it's what most vets reach for when they want a predictable result. It comes in individual 1g sachets, which sounds fiddly but actually makes dosing very clean. A box of 30 sachets runs around £22–25 on Amazon UK, so you'd be saving a meaningful amount over six weeks. The transition doesn't need to be gradual — you can just swap on day one since the format and delivery method are so similar to what he's used to.

Yes — the FortiFlora dosing is one sachet per day regardless of dog size, which is a quirk of the product but consistent with how the clinical trials were run. The strain concentration is high enough that one sachet covers large breeds effectively. If you ever want to double up during a period of stress — long travel, kennelling, a course of antibiotics — that's fine short-term, but day-to-day one sachet is the right call. Just sprinkle it straight onto his food the same way you've been doing with the Pro-Kolin powder and he should barely notice the difference.

You're in good shape — his gut is already stable, you're switching to a well-evidenced product in the same format, and you'll save around £10–12 per cycle. If for any reason his stools change in the first couple of weeks, it's worth waiting a full month before judging it, since probiotic effects can take a few weeks to settle in a new microbiome environment. But honestly, most dogs switch without a blip. Good luck with him.