RHODEDENDRON

Morphology• They are characterised by shrubs and small to (rarely) large trees• The leaves are spirally arranged. • Leaf size a can range from 1-2cm to over 50cm• They can be either evergreen or decidious.• The flowers are arranged in many clusters.

Toxicology• Some species are poisonous to grazing animals• Produce a toxin known as grayanotoxin in their pollen and necter• This disrupts sodium channels affecting the skeletal and cardiac muscles• If eaten via honey it has a slight hallucinogenic and laxative effect.• Is extremely toxic to horses• Some animals die within a few hours of digesting the plant. • Most horses tend to avoid it • As little as 3ml nectar/kg bodyweight or 0.2% of the bodyweight of leaves may be toxic or lethal

Signs and Symptoms• Drooling• Vomitting• Diarrhoea• Inappetince• Abdominal pain• Abnormal heart rate and rhythms• Hypotention• Weakness• Tremours• Depression• Blindness• Seizures • Coma

Treatment• Emesis is used where appropriate• Activated charcoal should be administered repeatedly the first day

• Fluid replacement therapy and respiratory support may be necessary. Atropine is recommended for severe bradycardia. Isoproterenol or sodium channel blockers may be used to treat the heart block