Chinaberry Poisoning in Dogs

The chinaberry tree is a member of the mahogany family that is native to Australia, China, and India. These deciduous trees sprout delicate light purple flowers in the spring, which develop into yellow, berry-like fruits in the summer. They were transported to North America in the early 1800’s as an ornamental plant, but has escaped into the environment and is considered an invasive species in several southern states. It produces a potent insecticide which utilizes a tetranortriterpene neurotoxin known as meliatoxin. This insecticide is found throughout the plant’s bark, leaves, and flowers but is found in the highest concentrations in the ripe fruit. If you suspect that your pet has consumed any of this plant, contact your veterinarian immediately.

The chinaberry tree, or Melia azedarach, is a deciduous tree that produces a potent insecticide which utilizes a neurotoxin that can prove detrimental to your pet if ingested.

Symptoms of chinaberry tree poisoning occur most often from eating the ripe fruit, however, the bark, leaves, and flowers also contain smaller amounts of the toxic substances. Symptoms usually begin within just two to four hours from ingestion.

• Abdominal pain
• Blood in stool
• Colic
• Constipation
• Death
• Depression
• Diarrhea        
• Excessive drooling
• Heart attack
• Hyperactivity
• Lack of coordination
• Loss of appetite
• Muscle rigidity
• Seizures
• Slowed heart rate
• Stupor
• Vomiting
• Weakness

Types

The scientific name for the chinaberry tree is Melia azedarach, and it belongs in the mahogany family. Although the most common name by far is the chinaberry tree, it goes by several other names as well, including: 

• Bead tree
• Cape lilac
• Ceylon cedar
• China ball tree
• Paradise tree
• Persian lilac
• Pride of India
• Texas umbrella tree 
• White cedar

Another tree in the mahogany that produces a similar insecticide is the azadirachta indica, or neem tree. It is often confused with the chinaberry tree, however, the neem tree is much less toxic than the chinaberry tree. The neem tree, also known as nim tree or Indian lilac, and the oil from it is often used to protect crops from insects. The azadirachtin in the oil can cause contact irritation to the skin, and swallowing the oil can cause gastrointestinal irritation as well.

The toxin in the chinaberry tree is a tetranortriterpene neurotoxin known as meliatoxin, and it most is concentrated in the small ripe fruits of the tree. The toxin developed as a natural insecticide to protect the tree from predators. Although this neurotoxin is also present in the leaves, bark, and flower of this plant, it is generally not in high enough concentrations to cause severe toxicity. This tree was brought to the United States sometime in the early 1800’s and has become an invasive species in some areas of the southern US since then. The seeds of the chinaberry tree are rapidly spread by birds who are immune to the toxin in the fruit. The branches with dried berries still attached are sometimes used in floral arrangements, and the seeds were often used to make rosaries. Although the dried berries are less toxic than fresh, your veterinarian should still be contacted in the event that your pet eats the dried berries as well.

If you believe your pet has ingested part of the chinaberry plant do not hesitate to contact your veterinarian, especially if the fruit or seed may have been consumed. The meliatoxin from ingesting the fruit of the chinaberry tree is often fatal within twenty-four hours without supportive care seeking that treatment early is the best course of action for a positive outcome. If you see your pet consuming the fruit from the chinaberry tree identification is often all that is required for diagnosing the source of your pet’s distress. If you didn’t witness the ingestion of the plant, the symptoms will alert the veterinarian to delve further into opportunistic eating that was witnessed in addition to verifying any concurrent prescriptions or supplements that your dog takes in an attempt to determine which drug or toxin is triggering the symptoms. Biochemistry profile, complete blood count, and urinalysis assessments are likely to be completed at this time for further evaluation.

Your dog is likely to be admitted into the veterinary hospital immediately upon diagnosis for supportive therapy as it is needed to give the patient the best chance at survival after ingestion of this toxin. If the time since ingestion has only been a few hours your veterinarian may instruct you on how to make your dog vomit before coming in. Once at the office a gastric irrigation, usually done with the use of general anesthetic, may be recommended as well to ensure as much of the plant material is removed from the system as possible. Activated charcoal will also be given to your pet at this point to soak up as much of the meliatoxin as possible before it passes into the bloodstream. The supportive treatment will include IV fluids for dehydration as well as electrolytes and sugars to regulate any imbalances that occur. Oxygen will be available if breathing becomes labored, and pain management and gastroprotective medications may also be administered to counteract symptoms.

Ensuring that a calm and quiet environment is available for your pet to return home to will help speed their recovery. Plenty of fresh water should be made available and extra bathroom breaks should be expected. Patients that are recovering from anesthesia for gastric lavage may find coordination to be more difficult when they first get home, and will often show confusion and disorientation. Isolation from other pets and from children is advised until the medication has fully cleared your companion’s system. Your veterinarian may recommend more frequent monitoring of your pet’s blood chemistry levels as well, particularly in relation to liver and kidney functionality or impairment.