Is Day-Blooming Jessamine Poisonous? – Toxicity to Pets and Humans

Day-blooming jessamine is toxic to dogs, cats, horses, and humans. The entire plant, including the white flowers, leaves, and small berries, contains vitamin D glycosides that disrupt calcium regulation in the body. Horses and livestock are most at risk from grazing exposure, but dogs and cats can be seriously harmed, and the berries pose a danger to young children who may mistake them for edible fruit.

What Makes Day-Blooming Jessamine Toxic?

The plant (Cestrum diurnum, in the nightshade family) contains glycosides that mimic the action of active vitamin D (calcitriol) in the body. When ingested, these compounds cause the intestines to absorb far more calcium than normal, producing a state of hypercalcemia. Over time or in high doses, excess calcium deposits in soft tissues including the kidneys, blood vessels, and lungs, a condition called calcinosis.

The berries, leaves, and stems all carry the toxic glycosides. The berries are small and dark when ripe, and their appearance can attract children and pets.

Symptoms of Day-Blooming Jessamine Poisoning

Dogs and cats

• Loss of appetite and lethargy
• Vomiting and diarrhea
• Excessive thirst and urination
• Weakness and muscle pain
• In severe or prolonged exposure: weight loss, difficulty breathing, and tissue calcification

Acute poisoning is possible from a single significant ingestion, but the hypercalcemia syndrome can also develop gradually with repeated low-level exposure.

Humans and children

• Nausea, vomiting, and abdominal pain after ingestion of berries or leaves
• Muscle weakness and fatigue
• Confusion in larger exposures
• Young children who eat the berries are at highest risk

Skin contact with the plant can cause mild irritation in sensitive individuals, though this is far less dangerous than ingestion.

What to Do

1. Remove any remaining plant material from the mouth.
2. Do not induce vomiting unless directed by a professional.
3. Call poison control at 1-800-222-1222 (US) or your vet immediately.
4. Take a photo of the plant or bring a sample to help with identification.
5. For pets, veterinary treatment may include IV fluids and medications to manage calcium levels.

Hypercalcemia can cause kidney damage and is a veterinary emergency. Do not wait for symptoms to worsen before seeking help.

Safe Handling and Alternatives

Day-blooming jessamine is a warm-climate shrub sometimes grown as an ornamental for its fragrant white tubular flowers. In regions where it grows outdoors, it can spread into gardens without being recognized as dangerous.

• Do not plant in yards where pets roam or children play.
• Wear gloves when handling or pruning; wash hands afterward.
• If you have an established plant and pets or young children, consider removing it.
• Night-blooming jessamine (Cestrum nocturnum) is a closely related species with a similar toxicity profile.

Frequently Asked Questions

Is day-blooming jessamine the same as night-blooming jessamine? No, though they are closely related. Both are Cestrum species and both are toxic. Day-blooming jessamine (C. diurnum) produces white flowers that open in daylight; night-blooming jessamine (C. nocturnum) flowers at night and has a stronger scent.

Are the berries the most dangerous part? The berries, leaves, and stems all contain toxic glycosides. The berries are a particular concern because children and animals may eat them. Treat the entire plant as poisonous.

My dog ate a few berries. Is this an emergency? Call your vet immediately. Even a small ingestion warrants prompt evaluation because the glycoside toxicity can cause kidney damage and electrolyte imbalance. Early treatment improves outcomes significantly.

How long does it take for symptoms to appear? Symptoms of hypercalcemia can develop hours after ingestion and may worsen over the following day. If you witnessed ingestion, contact a vet before symptoms appear rather than waiting.