Is Thalictrum flavum subsp. glaucum toxic to cats?

Mildly. The ASPCA lists thalictrum flavum subsp. glaucum as mildly toxic to cats — a chewing cat typically gets mouth irritation, drooling, and vomiting rather than a medical emergency, but it is still best kept out of reach. Thalictrum is not individually listed on the ASPCA toxic or non-toxic plant lists. As a buttercup-family (Ranunculaceae) plant it contains protoanemonin and alkaloids, irritant compounds that can cause oral and gastrointestinal upset if eaten and skin irritation on contact; treat with caution, wear gloves when cutting it back, and verify with a vet if a pet ingests it.

Thalictrum is not individually listed on the ASPCA toxic or non-toxic plant lists. As a buttercup-family (Ranunculaceae) plant it contains protoanemonin and alkaloids, irritant compounds that can cause oral and gastrointestinal upset if eaten and skin irritation on contact; treat with caution, wear gloves when cutting it back, and verify with a vet if a pet ingests it. Signs usually appear soon after chewing rather than hours later — watch for drooling, pawing at the mouth, vomiting, loss of appetite, or unusual lethargy after your cat has had access to thalictrum flavum subsp. glaucum.

Stay calm. Remove any plant from your cat's mouth and take the plant away. Note how much was eaten and when, and do not induce vomiting unless told to. Call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 and follow their advice; a leaf or photo helps the vet treat it correctly.

The ASPCA classification Growli uses applies to both cats and dogs: Thalictrum flavum subsp. glaucum is mildly toxic to dogs as well. See the full thalictrum flavum subsp. glaucum pet-safety guide for both species.

For a similar look without the risk, see the best cats-safe plants list — every plant there is ASPCA non-toxic to cats and dogs.