Eucalyptus Poisoning in Dogs

The eucalyptus plant is the major source of eucalyptus oil, which is used in many products for its antiseptic properties, scent, and flavoring. When ingested in sufficient amounts this oil, eucalyptol, is an irritant to the gastrointestinal system, causing discomfort, vomiting, and diarrhea. It is also a neurotoxin and can cause neurological symptoms as well, such as depression, confusion, and seizures. If your dog has ingested any part of the eucalyptus plant or a product containing eucalyptus oil it is important to contact your veterinarian as soon as possible.

Eucalyptol, the chemical in eucalyptus, is a gastrointestinal irritant and a neurotoxin. If your dog consumes either the plant or products containing eucalyptus oil, contact your veterinarian immediately.

Ingestion of eucalyptol can result in both gastrointestinal and neurological damage, and the symptoms may sometimes be delayed for a few hours. Signs that your pet may have ingested an overdose of eucalyptus oil can include:

• Confusion
• Depression
• Dilated eyes
• Diarrhea
• Difficulty swallowing
• Excessive drooling
• Lethargy
• Loss of appetite
• Low blood pressure
• Muscle weakness
• Pawing at mouth (burning in mouth) 
• Pinpoint pupils
• Rapid or shallow breathing
• Rapid or weakened heart rate
• Seizures
• Slowed reflexes
• Vomiting
• Wheezing        

In addition to these symptoms, undiluted eucalyptus oil may cause itching, redness, and swelling of the exposed skin if in contact with it. 

Types

The natural compound of eucalyptol is found in several plants, though usually in much smaller concentrations. 

Plants that contain eucalyptol include:

• Bay leaves 
• Camphor laurel
• Cannabis sativa (strain specific)  
• Cherry laurel
• Common sage 
• Mugwort
• Rosemary
• Sweet basil
• Tea tree
• Wormwood

Most of these plants, such as sweet basil or cannabis, have extremely minute amounts of the chemical. A few, such as the laurel plants, wormwood, or mugwort, can cause the same dangerous symptoms as the eucalyptus plant. As this toxic oil can be found in numerous plants and products, if your pet exhibits signs of poisoning, it is essential to contact your veterinarian as soon as possible.

The oil from the eucalyptus plant is eucalyptol, also known as cineole. Although it is toxic when undiluted it is also a very useful liquid. It is an antiseptic and has been used to treat skin disorders, bad breath, coughs, and congestion for centuries. As such, it is found in a number of products, from insect repellents to cough drops. Commonly known products such as Listerine and Vicks VapoRub include large amounts of this oil and it is even included in minute amounts in some food products. Although ingestion of the plant itself can certainly be the cause of poisoning, eating products made with moderate to high concentrations of this useful but volatile chemical will result in toxicity as well.

If you witnessed your pet consuming the plant or product containing eucalyptus oil, then the identification of the item eaten may be all that is required for diagnosing the origin of your pet’s affliction. If the cause of the toxicity is not immediately known your veterinarian will question you regarding any opportunistic eating that may have occurred as well as any prescriptions or supplements that you or your dog is taking to determine if they may contain the toxin. If your canine ingested a product with the eucalyptus oil, the packaging will help the veterinarian get an idea of how much of the actual chemical was ingested as well as alerting them to any additional toxins in the product. Many of the symptoms are similar to symptoms and signs of other types of neurotoxins. The aroma the oil produces is rather distinctive, however, and can frequently be smelled on the patient’s breath, or in the urine.

Due to the caustic nature of Eucalyptus oil, it is not recommended to induce vomiting in the event of an overdose as this can cause further damage. If there is any oil that is still remaining on the skin or in the eyes, the area should be thoroughly rinsed to avoid adverse local reactions. Treatment at the veterinary hospital is likely to start with gastric lavage followed by the use of activated charcoal to soak up any remaining toxin. In the case of Eucalyptus oil ingestion, it is particularly important that the gastric lavage be done under general anesthesia, and there is a risk of exposure of the windpipe and lungs to the Eucalyptus oil. General supportive measures will likely include IV fluids for dehydration and combinations of sugars and electrolytes to adjust any imbalances. Laxatives and stimulants may be given to help speed the toxin through the system, and antihistamines and pain medications may be recommended to reduce any itching, swelling, or pain.

Ensuring that the environment that the patient will be using for recovery is a quiet and calm setting will help to speed recovery. Adequate amounts of fresh water should be made available and extra bathroom breaks should be expected. Patients that are recovering from anesthesia given for a gastric irrigation may have coordination difficulties at first, and are often initially confused and disoriented. In addition, drowsiness from the disturbance to the central nervous system may continue for a few days. Isolation from other pets and from children is generally suggested until both the medication and the toxin have had a chance to fully clear out of your companion’s system.