Coriander is one of the safer herbs in the kitchen
Coriander — the fresh leafy herb also called cilantro, plus the milder dried seed used as a spice — is generally considered safe for dogs in small quantities. It is not on the list of plants owners are warned away from, and a few leaves chopped over a dog's dinner will not harm a healthy dog. That said, safe does not mean necessary. Coriander adds flavor interest and a little variety to a bowl, but your dog's complete food already covers his nutritional needs, so treat the herb as an occasional garnish rather than an ingredient to build meals around.
Leaves, seeds, and the preparations to avoid
Fresh leaves and stems, washed and chopped, are the gentlest form to offer. A pinch of plain ground coriander seed stirred into food is also mild. Where coriander becomes a problem is the company it keeps. Curry pastes, spice blends, marinades, and takeaway sauces combine coriander with onion, garlic, chili, and salt, none of which belong in a dog's bowl. A dog should never be offered leftover curry or seasoned rice on the logic that coriander itself is safe — the blend is what he would actually be eating.
Also skip coriander growing wild or gathered outdoors unless you are certain of the plant. Several common look-alike plants are unsafe, and a garden herb you grew yourself is the only foraged version worth trusting.
How much to offer, and how dogs tend to react
Start with a few chopped leaves for a medium dog, less for a small one, mixed into food rather than offered as a pile. Some dogs eat coriander happily, while others pick around it or refuse the bowl — the herb has a strong, divisive flavor that many dogs find soapy and strange, and forcing the issue gains nothing. If he leaves it, believe him.
Introduce it on its own, not alongside three other new foods, so that if his stool loosens you know the likely cause. A large helping of any unfamiliar herb can mildly upset the stomach, so more is not better here. Dogs with sensitive digestion, and dogs on prescribed diets, do fine without herbal extras at all; check with your veterinarian if you are unsure whether garnishes fit your dog's plan.
When a herb stops being a small question
Contact your veterinarian if your dog eats a large amount of any seasoned dish containing coriander alongside other spices and then vomits, develops diarrhea that does not settle, or seems uncomfortable. Be ready to describe the whole dish, not just the herb, because onion or garlic in the same meal changes the clinic's concern. A dog who has grazed an unknown outdoor plant and then drools, retches, or seems unwell also deserves a prompt call, with a photo of the plant if you can take one safely.
For the common case — a few leaves of home-grown coriander in a normal meal — no worry is needed. This is one of the calmer questions in the can-dogs-eat family.
Noting a mild preference so meals stay consistent
If your dog turns out to like a little chopped coriander, that preference is worth passing on accurately. Record in KinsLe's Care Teams that a few fresh leaves are acceptable on your dog's food while spiced blends are not, so a helper does not reach for a curry paste by mistake.