Elderberry Poisoning in Dogs

Plants in the Sambuca family, also known as elderberry plants, are toxic in almost all portions of the shrub. Although ripened elderberries are frequently used to make wine, jellies, and desserts the elderberry plants themselves contain amygdalin, a cyanogenic glycoside that produces hydrogen cyanide in the digestive tract. Ingestion of any part of this plant can be fatal in less than an hour with the possible exception of the fully ripened fruit. If your pet has eaten any portion of this plant it should be treated as an emergency. Prompt treatment is the patient’s best chance at survival.

Elderberry plants are in the Sambuca family. This plant produces cyanide when ingested, which is highly toxic and can cause death within less than an hour if left untreated.

Elderberry plants are toxic due to amygdalin, a cyanogenic glycoside that is present throughout the plant, except in the ripe berries. Teas and syrups made from elderberry leaves are also toxic can potentially cause fatalities in humans. Signs of cyanide toxicity can occur within 15-20 minutes after consuming the elderberry plant and without treatment death can occur within just 30-45 minutes. 

• Cherry red blood
• Coma
• Dilated pupils
• Diarrhea
• Difficulty breathing
• Drop in blood pressure
• Excessive drooling
• Fluid accumulation in chest or abdomen
• Nausea
• Rapid heart rate
• Seizures
• Shock
• Smell of bitter almonds on breath
• Sudden death
• Tremors
• Vomiting

Types

There are a few varieties of the elderberry plant in the Sambuca family. They include: 

Black Elderberry- Also known as common elderberry, the berries of this plant can be eaten when ripe, but the unripe berries and the rest of the plant are still toxic. The flavor of elderberries can be unpalatable to most, and cooking or drying is usually recommended.

Red Elderberry- This is the elderberry that is most commonly used for elderberry wine. Berries from red elderberry varieties should not be eaten unless deseeded and then thoroughly cooked or fermented.

Blue Elderberry- Like the black elderberry, the berry of this plant is safe when ripened, though cooking or fermenting is often recommended to bring out the berry’s sweeter side.  

“Sutherland Gold” Elderberry- A variety of red elderberry, notable for the fact that even the ripened berries of this plant are toxic and should not be ingested.

The toxin produced by the elderberry plant is a cyanogenic glycoside known as Amygdalin, the same toxin that is found in bitter almonds, stone fruits, and apple seeds. Degradation of the amygdalin in the digestive tract produces hydrogen cyanide. Hydrogen cyanide is toxic in as little as two milligrams per kilogram of weight for almost all animal species. Death from cyanide poisoning is generally rapid, usually occurring in less than an hour from ingestion.

If you believe your pet has ingested any part of an elderberry plant do not hesitate to contact your veterinarian. Cyanide toxicity from ingesting any portion of the plant material can be rapidly fatal and seeking early treatment is essential. If you witnessed the consumption of the plant material, then plant identification 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 want to get information about opportunistic eating that may have occurred as well as any prescriptions that your dog is taking. Many of the symptoms are similar to symptoms and signs of other types of poisoning, however, certain symptoms such as the cherry red blood and the smell of bitter almonds on the breath, are more unique to cyanide poisonings. Cyanide can be detected in the blood and the urine in the first few hours post death, but if cyanide exposure is suspected treatment is generally begun without waiting for the result.

Because of the rapid onset of symptoms relating to cyanide poisoning, treatment needs to be initiated as soon as possible. Exposure to toxic cyanogenic glycosides is likely to be fatal without prompt treatment, but the outcome is often much improved. Amyl nitrate will generally be administered, often accompanied by thiosulfate treatment in the form of an IV injection. In some cases, where cyanide exposure is likely but unconfirmed, thiosulfate has been used independently with some success. These antidotes to the cyanide produced in the gut are generally quite effective, as long as the heart is still beating, however caution is indicated as the antidotes are also toxic on their own. Vitamin B12 may also be utilized as it is known to bind to the cyanide, producing cyanocobalamin which is then excreted in the urine. Additional treatments are supportive in nature. The supportive treatment will include IV fluids for dehydration as well as electrolytes and sugars to adjust for any imbalances. Oxygen therapy may also be used to help your pet recover. Administering oxygen has been shown to be particularly helpful for dogs and cats.

Untreated, poisoning by cyanogenic glycoside is almost always fatal. If you are able to get your canine companion into the veterinarian’s office quickly, recovery becomes much more likely. If your pet survives the first two hours, then full recovery is more likely. Prognosis once treatment has begun is dependent on the quantity ingested, the speed of initial diagnosis and treatment, and the size of the dog. It is possible for additional cyanide to be absorbed in the gastrointestinal tract after this time, causing a recurrence of the poisoning signs and symptoms. Your veterinarian will likely request a follow-up appointment to check for any further complaints, particularly neurological disturbances and behavioral changes.