It happens in the two seconds you looked at your phone or said hello to another dog: something's already in their mouth, or already gone. This is general awareness, not veterinary advice — if you're ever genuinely unsure, call your vet or an emergency vet line and let them decide, rather than a blog post.

The immediate few seconds

Staying calm actually matters here, not just as advice but practically — a dog that senses panic often swallows faster or runs off with whatever it is, which is the opposite of what you want. If it's still in their mouth and safe to do so, a calm "drop it" beats a lunge. If it's already gone, take a moment to actually note what it likely was, roughly how much, and when — that detail is exactly what a vet will ask for first, and it's much easier to remember in the moment than five minutes later.

The common London-specific hazards

Fox droppings. Foxes are everywhere in London's parks, and their droppings can carry parasites your dog can pick up from investigating or eating them too closely. Rarely an emergency, but worth a call to your vet about worming if it happens regularly, and worth actively discouraging when you see it starting.

Wild mushrooms after rain. Parks and commons produce a real flush of fungi after wet weather, and while most are harmless, some UK species genuinely aren't. Not identifiable reliably by a quick look, which is exactly why any mushroom your dog has actually eaten (rather than just sniffed) is worth a call rather than a guess.

Dropped food and takeaway waste. Pavements and park edges collect more of this than anyone really wants to think about — chocolate, grapes and raisins, and anything sweetened with xylitol (sugar-free gum is the most common source) are all genuinely toxic to dogs even in small amounts, not just "not great."

Cooked bones. Splinter risk rather than poisoning, but a real one — cooked bones (chicken especially) break into sharp fragments in a way raw bones generally don't.

When to call now, not later

A few signs are worth treating as "call immediately," not "monitor and see": vomiting that doesn't stop after one instance, obvious drooling or pawing at the mouth, sudden lethargy or wobbliness, visible distress, or any known ingestion of chocolate, xylitol, grapes/raisins, or an unidentified mushroom — even with no symptoms yet, since some of the most serious reactions are delayed rather than immediate.

Outside those, "seems fine, alert, eating and drinking normally" is usually genuinely fine — but a quick call to describe what happened costs a vet almost nothing to answer and can rule out a worry completely, which is worth it on its own.

Worth having ready before you need it

Your own vet's actual phone number, including whatever their out-of-hours arrangement is — most practices use a shared emergency line outside normal hours, and it's much easier to find that out now than mid-panic. A specialist animal poison advice line is also worth knowing exists, even if you never end up needing the number: a quick search for one before a walk, not during one, means it's there if a genuine question comes up that isn't quite emergency-vet-level but isn't nothing either.

Reducing it without becoming that owner

None of this is a training guide — teaching a solid "leave it" is a job for time, patience, and ideally a trainer who knows your specific dog — but the instinct worth building in yourself is noticing early rather than reacting late. A dog whose head suddenly drops toward something on the ground is giving you a half-second of warning most of the time, which is enough to intervene if you're actually watching rather than mid-scroll.

The part that doesn't change

Most walks pass without any of this happening at all, and the ones that do usually resolve as a phone call and a bit of a fright rather than anything worse. It's not a reason to walk more cautiously or less often — just a reason to actually know, before you need to, what the real red flags are and who you're calling if you see one.