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Is Rhododendron Toxic to Dogs?

☠️ ToxicSeverity: Moderate
✅ Cross-checked against veterinary poison-control guidance · Oct 2026 audit
⚠️ Educational info only. If your pet just chewed something and looks unwell, skip the reading and call your vet or Pet Poison Helpline (US): (855) 764-7661.
Yes, rhododendron is toxic to dogs. The leaves, flowers and nectar contain grayanotoxins that affect the heart and nervous system.

Also known as: Azalea, Mountain Rose, Rhododendron spp. · Rhododendron spp.

What makes it toxic

Grayanotoxins throughout the plant, concentrated in leaves and flowers. They overstimulate sodium channels in nerves and heart muscle, causing digestive upset and abnormal heart rhythm.

Warning signs to watch for

Drooling, vomiting and diarrhea within a few hours, then weakness, wobbliness, low blood pressure, a slow or irregular pulse and, in large ingestions, tremors and seizures.

What to do if your dog eats it

Clear plant material from the mouth and call your vet the same day. Treat any collapse, tremors or breathing trouble as an emergency and get the dog to an animal hospital immediately.

Common questions

How much rhododendron is dangerous for a dog?

There is no exact threshold, but even a small dog eating a handful of leaves or browsing a hedge for a while can develop real symptoms. Vets treat any confirmed chewing as a case worth calling about.

Are rhododendron flowers or leaves worse?

Both are toxic. Leaves are usually eaten in greater quantity and carry a high toxin load, while flowers and nectar are also poisonous.

Is a fallen petal in the yard a risk?

A single petal is unlikely to cause more than mild stomach upset in a dog, but sweep up fallen blooms and leaves so a bored dog cannot graze on them.

More plants checked for dogs

Pothos☠️ ToxicYes, pothos is toxic to dogs. Chewing any part of the vine releases calcium oxalate crystals thaAloe Vera⚠️ Mildly ToxicAloe vera is mildly to moderately toxic to dogs. The skin and latex layer of the leaf contain coSpider Plant✅ Non-ToxicNo, spider plants are non-toxic to dogs. A dog that nibbles the arching leaves is not at risk ofEaster Lily⚠️ Mildly ToxicEaster lilies are only mildly toxic to dogs — they usually cause stomach upset, not the fatal kiSago Palm☠️ ToxicYes — sago palm is severely toxic to dogs, with a documented fatality rate around 50% when untreBoston Fern✅ Non-ToxicNo, Boston ferns are non-toxic to dogs. Chewing a frond will not poison your dog.

This page is general educational information, not a substitute for professional veterinary advice. Every pet is different — if your animal ate something concerning, contact your veterinarian or a pet poison hotline right away. Checking what your pet can eat? Visit our sister site SafeOrToxic.