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.
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.
If ingested
Contact your nearest vet immediately
- Onset
- Right away to within 2 hours of ingestion
- Symptoms
- Photosensitivity, depression, vomiting
- Action
- Rinse the mouth with water and monitor. Consult a vet if symptoms last more than 12 hours.
Details
- Scientific name
- Hypericum perforatum
- Common name
- Klamath Weed
- Family
- Hypericaceae
- Toxic parts
- All parts
- Compounds
- Hypericin
- Onset
- Right away to within 2 hours of ingestion
- Symptoms
- Photosensitivity, depression, vomiting
- Action
- Rinse the mouth with water and monitor. Consult a vet if symptoms last more than 12 hours.
- Source
- ASPCA
Related plants
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