Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Oleander Toxicity


In temperate and sub-tropical climates white oleander is a common large ornamental shrub. Oleander is a very toxic plant and all parts of the plant must be kept away from horses. Horses that consume as little as one ounce of leaves can be poisoned.

Oleander toxicity is a known cause of sudden death in horses. Horses eating more than several ounces of oleander leaves may simply be found dead within 12 hours of ingestion.

If found before death, affected horses are likely to show signs of colic and diarrhea. Most will be in shock and have very high irregular heart rates, rapid or labored breathing, weakness and wobbliness, or can also be down and seemingly unable to rise. Convulsions are common preceding death.

DIAGNOSIS is by clinical signs in a horse that has had exposure to Oleander. Post-mortem, the diagnosis can be made through finding the plant in the stomach.

TREATMENT: There is no specific treatment for counteracting the effects of the toxins. Treatment is limited to supportive nursing care and symptomatic treatment.

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I might observe

You might make these observations when a horse has this condition.

Very Common
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Questions To Ask Your Vet:
  • Is it worth attempting to save my horse?
  • What steps should I take to avoid toxicity by Oleander and other poisonous plants?

Prevent your horses from all access to Oleander. Remove any oleander plants that your horse could POSSIBLY be exposed to or gain access to. Be sure any clippings or uprooted plants are disposed of in bags and sent to the landfill. Never allow your horse to eat any plant that you cannot identify and know is harmless.

All parts of the plant are toxic to horses, many other animal species, and humans too. So be sure to wear gloves when handling the plants and trimmings. Do not burn the plant material as apparently even the smoke is toxic.

Author: Doug Thal DVM Dipl. ABVP