Why only the Poodle matters here
The fact that your other dog didn't touch the cilantro means we can focus entirely on your 8 kg Poodle's situation. Unlike some shared foods where both dogs would need monitoring, cilantro itself isn't toxic to either pet. The real question is whether anything else was mixed in with those green leaves when they garnished the tacos.
Restaurant or homemade tacos often include onion or garlic in the seasoning blends or chopped into the garnish. Those are far more concerning than cilantro. Check any remaining garnish for white specks (onion) or strong odors (garlic), and estimate how much might have stuck to the leaves your dog consumed.
What half a handful does to a small dog
For an 8 kg dog, eating a few cilantro leaves is like you nibbling a sprig of herbs - barely noticeable. But if he ate a loose handful (about 10-15 leaves), the fiber and essential oils may cause mild digestive rumbling. The good news? Unlike rich human foods that trigger pancreatitis, cilantro's oils are gentle.
Watch for the classic signs of harmless herb overload: slightly softer stool tomorrow, perhaps a single episode of grass-eating as his system adjusts. These reactions don't mean poisoning - just a dog's version of "maybe I didn't need that third helping of salad."
When shared meals become separate concerns
Even though both dogs ate from the same table, their risks differ completely here. Your uneaten-taco dog needs no cilantro-related care, but do check both pets for taco ingredients like avocado pits or corn cobs if those were accessible. Shared meals often hide multiple hazards.
Isolation isn't necessary unless you suspect the cilantro was a vehicle for something toxic. Normal play and proximity are fine - the Poodle won't "shed" cilantro effects to his housemate. Just separate their water bowls if the cilantro-eater develops loose stool, to prevent cross-contamination of gut bacteria.
The 24-hour watch for stealth ingredients
Over the next day, the main task is confirming this was pure cilantro. Watch your Poodle for subtle signs of onion/garlic toxicity: gums turning pale pink, sudden fatigue during play, or orange-tinged urine. These would appear 12-24 hours post-meal and demand immediate vet care.
For true cilantro-only consumption, the timeline is shorter. Any stomach upset would manifest within 8 hours as a single vomit episode or soft stool. No symptoms by tomorrow morning? You've dodged the taco night bullet completely.
The full verdict, portion guidance and serving notes are collected on the Cilantro food facts page.