Rhododendrons (and their close relations the Azalea) are known to be toxic to various animals including dogs, cats, horses and even humans.  Different species of Rhododendron have different levels of toxicity and different parts of the plant are more dangerous than others too.  However, ALL parts of the plant from the green leaves (the most toxic), to the stems, the roots, the petals, the pollen and even water from blooms in a vase or any honey made from the nectar are poisonous.  In fact, just 0.2% of the plant to percentage of body weight is enough to illicit symptoms from your dog.

Time Frame:

Signs of toxicity can come on within an hour, but can take up to 12 hours to present.

Signs and Symptoms:

There are many signs that may indicate your dog is suffering from Rhododendron toxicity including:

  • Excessive Salivation
  • Vomiting
  • Diarrhoea
  • Abdominal Pain
  • Loss of Appetite
  • Tremors
  • Depression
  • Difficulty in Breathing
  • Abnormal Heart Rhythm and Fluttering (Atrial Fibrillation)
  • Abnormally Slow Heart Rate (Bradycardia)
  • Decrease in Blood Pressure (Hypotension)
  • Seizures
  • Coma
  • Death


First Aid:

It really is simply safest not to have Rhododendrons in your garden at all if you have dogs but, if you really can’t bring yourself to part with them, it is vital that they are segregated from your dog to prevent him coming into contact with them.  If he does, then getting him to the vet ASAP for treatment is vital – even if this is on an evening, please do not wait until the morning.

Your vet will wish to know a rough idea of how much has been consumed and what part of the plant your dog has been eating so if you can bring a portion of it with you, that would be helpful.  If that isn’t an option, then take a quick photo.

It is likely that he will be given something to induce vomiting and some activated charcoal to counteract the effects of the toxins, and also be placed on a drip to administer fluids if he has lost a lot of water due to diarrhoea/vomiting.