Pieris japonica
Japanese pearl flower, andromeda
Dense woody shrub up to 3m tall. Pointed ovoid leaves up to 7cm long growing in coronet form around the stem. Leaves various shades of green and may be variegated. Flowers white to pink, drooping in grape-like bunches. They bear a passing resemblence to true lily of the valley.
Do not confuse with true lily of the valley.
Throughout NZ. Ornamental plant found in gardens.
Non cumulative toxins including andromedotoxin (grayanotoxins), diterpenoid and related compounds. (Same toxin as rhododendron) These irritate the skin and mucous membranes. Andromedotoxins have a marked effect on the heart causing prolonged depolarisation and excitation. They bind to and modify sodium channels and favour calcium movement into the cells resulting in a positive inotropic effect. Poisonings occur throughout the year.
Livestock, especially ruminants (usually due to eating prunings thrown over the fence). In an incident in Southland, 50 of 700 ewes died.
Clinical signs include salivation (burning sensation in the mouth), vomiting, abdominal pain, diarrhoea, depression, dyspnoea, weakness, staggering, convulsions, prostration and death in 1 - 2 days. Bradycardia, hypotension and atrioventricular block are cardiotoxic effects.
Congestion of lungs, green froth around mouth and in trachea.
From history, clinical signs, post mortem findings (usually leaves in gut).
Metaldehyde poisoning, rhododendron poisoning, acute heart failure, thiamine deficiency and mechanical obstruction of upper airways.
Decontamination by gastric lavage, saline cathartic, activated charcoal and laxative. May use an emetic if there is no sign of convulsions. Supportive therapy including fluid replacement, respiratory support, atropine for severe bradycardia and isoprenaline may be indicated for heart block.
Poor.
Control access to plant or plant trimmings.
Conner H.E. The Poisonous Plants In New Zealand. 1992. GP Publications Ltd, Wellington
Surveillance 2005, 32(3) 13
4 October, 2007
