Klamath Weed
Hypericum perforatum · Hypericaceae
How it looks
St. John's Wort is a plant with small, yellow, star-shaped flowers that bloom in clusters at the branch tips. The leaves are small and oval, arranged opposite, and when held up to the light show tiny translucent dots (oil glands). It reaches 12-31 in (30-80 cm) tall and is common as a medicinal herb.
Mild caution — stomach irritation
All parts of Klamath Weed contain irritating compounds that can cause depression and vomiting if chewed. Most cats recover on their own, but as a caution-level plant it still calls for monitoring.
If ingested
Contact your nearest vet immediately
- Action
- Rinse the mouth with water and monitor. Consult a vet if symptoms last more than 12 hours.
- Symptoms
- Photosensitivity, depression, vomiting
- Onset (typical course)
- Right away to within 2 hours of ingestion
Guide for parents
An occasional nibble on Klamath Weed rarely leads to serious trouble, but its hypericin can irritate the stomach and mucous membranes, causing mild gastrointestinal upset.
Make a habit of clearing away fallen leaves and broken stems the same day, and keep the pot somewhere your cat can't reach.
If symptoms last more than 12 hours or your cat shows a marked loss of appetite, consult your vet.
Details
- Scientific name
- Hypericum perforatum
- Common name
- Klamath Weed
- Family
- Hypericaceae
- Toxic parts
- All parts
- Compounds
- Hypericin
- Source
- ASPCA cats plant list
Related plants
Related guides
Top 10 Flowers Dangerous to Cats — The Ones You See at Florists
Ten flowers you'll commonly find at florists and grocery stores that are toxic to cats. Check before you receive them, and before you bring them home.
Got a Bouquet? What to Do If You Have a Cat
A bouquet is a lovely surprise — but if you live with a cat, there are a few things to take care of right away. From checking what's in the arrangement to choosing the right vase, here's what actually helps, in order.
Why Cats Chew Plants, and How to Stop It
A cat chewing and tearing at plants isn't just mischief — there's an instinct behind it. Once you understand why, the ways to stop it follow naturally.