✕ Toxic

Japanese Pieris

Pieris japonica

Japanese Pieris (Pieris japonica), also known as Lily of the Valley shrub or Andromeda, is a highly toxic ornamental shrub closely related to Rhododendron and Azalea. It contains grayanotoxins — the same diterpenoid polyol compounds responsible for Rhododendron poisoning — throughout all parts of the plant, including leaves, flowers, and nectar.

Important Notes

Toxic compounds: grayanotoxins I, II, and III (diterpenoid polyols); all parts toxic including nectar

Mechanism: grayanotoxins bind to voltage-gated sodium channels, keeping them open; this causes persistent depolarisation of cardiac and skeletal muscle, leading to hypotension, bradycardia, and arrhythmias

Symptoms: profuse drooling, vomiting, diarrhea, severe weakness, loss of coordination, abnormally slow heart rate, low blood pressure, tremors, seizures; can be fatal

Even small ingestions can cause serious cardiac effects in cats

Any suspected ingestion is a veterinary emergency requiring immediate care

Potentially Toxic Parts

Stem

Leaf

Entire Plant

Flower

Possible Symptoms Reported in Cats

Weakness, Tremors, Seizures (Convulsions), Ataxia (loss of coordination), Depression, and Coma

Neurological · 1–4 hours.

Vomiting, Diarrhea, Hypersalivation (Drooling), and Anorexia (Refusal to eat)

Gastrointestinal · 1–4 hours (occasionally up to 12 hours).

Cardiac Arrhythmias, Bradycardia (slow heart rate), Tachycardia (fast heart rate), and Hypotension (low blood pressure)

Cardiac · 1–4 hours.

Dyspnea (Difficulty breathing)

Respiratory · 1–4 hours.

Transient Blindness / Blurred Vision

Neurological · 1–4 hours.

Disclaimer: This summary was compiled from multiple sources and is for informational use only. It is not a diagnosis or treatment plan. Toxicity can vary based on the substance, amount, plant part, and individual cat. If you think your cat may have been exposed to a toxic substance, contact a veterinarian right away.