Before your cat comes home: the plant check
Walk through the house with this list. Three groups: plants that must leave, plants that must be locked away, and the ten most common plants you can keep. Every grade is transcribed from ASPCA and Pet Poison Helpline records and reviewed before publication — nothing here is opinion.
S4 · EMERGENCY Must go — give these away before the cat arrives
Azaleas and rhododendrons are life-threatening to cats (S4 Emergency): the grayanotoxins in every part of the plant can cause vomiting, weakness, low blood pressure, coma, cardiovascular collapse, and death, and the ASPCA warns that eating only a few leaves can cause serious problems.
Carolina jessamine (Gelsemium, also sold as yellow jessamine or Carolina jasmine) is life-threatening to cats (S4 Emergency): Pet Poison Helpline records that all parts of the vine contain neurotoxins that can cause muscle weakness, paralysis, slowed breathing, seizures, and death — it is not a true jasmine.
Daylily plants of the Hemerocallis genus are life-threatening to cats (S4 Emergency): any amount of leaf, stem, flower, pollen, or even vase water can cause acute kidney failure, and death is possible without early treatment — the same danger as true lilies, in a different genus.
Desert Rose (Adenium obesum) is toxic to cats (S4 Emergency): the ASPCA records vomiting, diarrhea, anorexia, depression, irregular heart beat, and death.
Lily plants of the Lilium genus are life-threatening to cats (S4 Emergency): any amount of leaf, stem, flower, pollen, or even vase water can cause acute kidney failure, and death is possible without early treatment.
Sago palm is life-threatening to cats (S4 Emergency): every part of the plant — the seeds most of all — contains cycasin, and any amount can cause liver failure and death, with symptoms sometimes delayed for hours.
S3 · TOXIC Out of reach, or out of the house
Amaryllis is toxic to cats (S3 Toxic): its lycorine and related alkaloids cause vomiting, drooling, abdominal pain, and tremors, and larger doses can bring seizures, a drop in blood pressure, and depressed breathing — despite names like belladonna lily, it is not a true lily.
Toxin: lycorine and other phenanthridine alkaloids; raphide oxalate crystals (concentrated in the bulbs)
Brunfelsia — sold as yesterday-today-and-tomorrow, lady of the night, or Paraguayan jasmine — is toxic to cats (S3 Toxic): every part contains brunfelsamidine and hopeanine, which cause vomiting, tremors, loss of coordination, and seizures that can last for several days; it is not a true jasmine.
Toxin: brunfelsamidine; hopeanine
Cyclamen is toxic to cats (S3 Toxic): its terpenoid saponins cause drooling, vomiting, and diarrhea from the leaves and flowers, but the tuber is the danger — a large amount of tuber can cause heart rhythm abnormalities, seizures, and death.
Toxin: terpenoid saponins
Daffodils are seriously toxic to cats (S3 Toxic): their lycorine and other alkaloids cause vomiting, drooling, and diarrhea, large ingestions can trigger convulsions and cardiac arrhythmias — and the bulb is the most poisonous part.
Toxin: lycorine; other alkaloids
Dieffenbachia (Dieffenbachia spp.) is toxic to cats (S3 Toxic): insoluble calcium oxalates cause mouth and throat irritation, and Pet Poison Helpline says death has rarely been reported with ingestion of Dieffenbachia plants.
Toxin: insoluble calcium oxalates; proteolytic enzyme
Hyacinths are seriously toxic to cats (S3 Toxic): their narcissus-like alkaloids can cause intense vomiting, bloody diarrhea, depression, and tremors — and the toxin is most concentrated in the bulb.
Toxin: possibly narcissus-like alkaloids
Kalanchoe is toxic to cats (S3 Toxic): its bufadienolides are heart toxins; eating it most often causes vomiting and diarrhea, the ASPCA lists abnormal heart rhythm (rare), and Pet Poison Helpline warns that if a large enough amount is ingested, changes in heart rate and rhythm, weakness, and collapse are possible.
Toxin: bufadienolides
Lily of the valley (Convallaria majalis, not a true lily) is toxic to cats (S3 Toxic): its cardenolides are heart toxins, and the signs on record include vomiting, an irregular heartbeat, low blood pressure, weakness, disorientation, seizures, and coma.
Toxin: cardenolides (convallarin and others)
American mistletoe is toxic to cats (S3 Toxic): its lectins and phoratoxins cause vomiting and diarrhea, and larger amounts can slow the heart, drop blood pressure, and make breathing difficult — a holiday sprig with berries needs to stay out of reach, not just out of sight.
Toxin: toxalbumin, pharatoxin viscumin (lectins, phoratoxins)
Shamrock (Oxalis) is toxic to cats (S3 Toxic): a small bite causes immediate mouth pain and stomach upset from its soluble calcium oxalates, and the ASPCA lists kidney failure as rare in dogs/cats, possible if significant amounts are eaten — Pet Poison Helpline adds that when large enough quantities are ingested, neurologic signs and kidney injury can follow.
Toxin: soluble calcium oxalates
Tomato plants are toxic to cats (S3 Toxic): the solanine in the leaves, stems, and green fruit can cause drooling, severe stomach upset, weakness, dilated pupils, and a slow heart rate — the ripe fruit is non-toxic on the ASPCA record.
Toxin: solanine (glycoalkaloids)
S0 · SAFE Keep — the ten most-searched plants graded safe for cats
- Orchid Phalaenopsis spp.
- Rose Rosa spp.
- Spider Plant Chlorophytum comosum
- Money Tree Pachira aquatica
- Sunflower Helianthus angustifolius
- Bamboo Phyllostachys aurea
- Rosemary Rosmarinus officinalis
- Calathea Calathea spp.
- Boston Fern Nephrolepis exaltata bostoniensis
- Hoya Hoya carnosa
S0 means non-toxic on record; a big meal of any plant can still upset a stomach. The full index has 45 S0 plants — scan the code for the rest.
IF IT HAPPENS ANYWAY Two hotlines, 24/7
S4 contact: go to a vet or emergency animal hospital immediately — do not wait for symptoms. Bring a photo or a piece of the plant.