Highly toxic — can be fatal
Yes — the sago palm is one of the most dangerous plants for both dogs and cats. Every part is toxic, the seeds especially, and it causes severe liver failure. Even a few seeds can be fatal.
Sago palms (Cycas species) contain cycasin and other toxins that attack the liver and nervous system. The seeds are the most poisonous part, but leaves and trunk are dangerous too. Poisoning causes vomiting, then liver damage that can progress to failure; survival rates even with aggressive treatment are sobering, which is why prevention matters so much. These plants are popular houseplants and garden plants in warm climates worldwide.
Both dogs and cats are seriously affected, and dogs are commonly poisoned because they chew the seeds. There is no safe amount for either species.
This is an emergency — call your vet or a poison helpline immediately if you suspect your pet chewed any part of a sago palm. Early decontamination and intensive liver support give the best chance. The safest course is not to keep sago palms where pets can reach them.
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General information, not veterinary advice. If your pet has eaten a toxic plant or shows symptoms, contact your vet or a pet poison helpline immediately. Full disclaimer.