Orange Poisoning in Dogs

The orange tree is a small tree that usually grows up to 25 feet, but some may actually reach 50 feet tall. It has deep green oblong leaves that feel leathery and average about six inches long, sweet smelling white flowers, and the round orange fruit is approximately five inches wide. The fruit is well-known around the world as a delicious form of vitamin C and is used to make many things from juice to perfume. The orange blossoms are well-known for their scent and essential oils, and they are the state flower of Florida. Unfortunately, these blooms are toxic to pets, as well as the fruit, foliage, and bark. They may not cause noticeable damage right away, but the effects may be seen later in life from changes to DNA and photosensitivity which can cause serious sun damage and possible skin cancer.

Orange poisoning in dogs is rarely fatal, and is only mildly toxic to your pet does unless he consumes a large amount. The main toxicity is in the orange peel, which is also a choking hazard because it is so thick and hard to digest. As a matter of fact, many dog owners feed their dogs orange slices as treats and, while this is technically not poisonous, it is not recommended by most veterinarians.

The symptoms of orange poisoning in dogs vary, but the most common are:

• Drooling
• Weakness
• Muscle spasms and tremors
• Vomiting
• Diarrhea
• Depression
• Choking on orange peel
• Potential photosensitivity
• Intestinal obstruction 

Types

The Orange tree is known botanically as Citrus sinensis of the Rutaceae family. There are many types of citrus varieties in the Rutaceae family, some which may be mistaken for the orange tree, but only the Citrus sinensis is the true orange tree. Some of the most common names the tree is known by are:

• Sweet orange
• Citrus aurantium
• Navel orange
• Orangenbaum

While there are quite a few possible toxic compounds in the orange tree, not all of them are dangerous to dogs. The most commonly listed dangers to dogs are:

• Biphenyl - A mildly toxic organic compound with a pleasant smell
• Citric acid - Is capable of causing shortness of breath, cough, and abdominal pain
• Coumarins - Makes the skin sensitive to sunlight. This includes Bergapten, which has been used for tanning purposes in humans
• Limonene - Sometimes referred to as d-limonene, which is a cyclic terpene that is a skin and respiratory irritant that may cause renal cancer in dogs; limonene is metabolized by the liver, causing liver damage or failure
• Psoralen - Can create a photosensitivity in dogs that may cause cancerous changes in the DNA and a higher susceptibility to skin cancer
• Synephrine - Has been linked to strokes, cardiac fibrillation, and respiratory distress
• Volatile oils - Are skin and eye irritants

To diagnose your pet, the veterinarian will need as many details as you can provide about the type of plant your dog ate (a photo or sample is excellent), when and how much was consumed, and any side effects that you have noticed so far. It is also helpful if you bring your pet’s medical and immunization records. Also, be sure you tell the veterinarian if your dog is on any kind of medication whether it is an over the counter drug or prescription. Mention if your dog has had any recent illnesses, strange behavior, or change in appetite.

The veterinarian will give your dog a thorough physical examination including oxygen level, breath sounds, blood pressure, body temperature, reflexes, pulse and respiratory rates, weight, coat and skin condition. In addition, the veterinarian may use an endoscope (long and flexible lighted tube) to get a good view of your pet’s throat, esophagus, and upper airway, looking for inflammation or obstructions. The endoscope is hollow so, if there is any foreign material, the veterinarian will be able to insert a tool to remove it. If your dog is experiencing any type of cardiac symptoms, an EKG (electrocardiogram) may be done to check the electrical and muscle functions for any abnormalities. Blood and urine tests will also be done at this time, including a CBC, blood glucose, and serum biochemistry profile. Additional tests that may be needed are x-rays, CT scan, MRI, and ultrasound.

Treating orange tree poisoning is similar to other poisoning cases, which usually include elimination of the poison, detoxification, medication, and observation.

Elimination

The veterinarian will give your dog an emetic (peroxide or ipecac) to induce vomiting and activated charcoal to absorb toxins that have not been absorbed yet.

Detoxification

A gastric lavage may be done to rinse away any undigested plant particles and fruit residue. Intravenous (IV) fluids will be given to flush the kidneys and rehydrate your pet.

Medication

Antiemetics may be given if your dog is still vomiting, stomach protectants for gastric distress, and cortisone cream for dermatitis.

Observation

Hospitalization for observation is usually not necessary so your veterinarian will probably send you home right away to observe on your own.

In the first few days, you should spend a fair amount of time with your dog to observe his behavior and recovery, and to provide plenty of fresh water as well as food that is easy to digest. Be sure to call your veterinarian without delay if you have any questions.