Ambrosia Mexicana Poisoning in Cats

Ambrosia Mexicana plants get their toxic abilities, not from inherited lethal chemicals, but the environmental factors the plant developed in. Like several other Chenopodiaceae plant species, the Ambrosia contains cyanogenic glycosides, nitrates, and oxalates, which do not generally cause harm in low quantities. Plants naturally possess these chemicals as regular functioning elements and remain low under normal growing conditions. An animal can eat these plants of low chemical value and, in most cases, their bodies will naturally separate the chemicals into waste products. However, plants that grow in harsh environments, like in times of drought or desert-like conditions, the chemical levels raise to lethal levels. If a cat consumes these lethal chemicals, the nitrate will transform to nitrite and it will be absorbed in the bloodstream and reduce the feline’s ability to transport oxygen. The end result is fatal as the consumed Ambrosia Mexicana plant has caused the feline to suffer nitrate poisoning. 

Ambrosia Mexicana poisoning in cats is a form of plant toxicity caused by the direct or indirect ingestion of the Ambrosia Mexicana plant. The Ambrosia Mexicana is part of the Chenopodiaceae family and can be identified by its scientific name: Chenopodium botrys. The Ambrosia Mexicana may be known by its other names, Jerusalem Oak or Feather Geranium. This plant is highly adaptable, can grow in a variety of soil types and is found throughout the world, including North America. The Ambrosia Mexicana is highly toxic to felines, humans, dogs and ruminants, such as sheep or cattle.

The symptoms of Ambrosia Mexicana Poisoning in cats often appear suddenly, as the nitrate causes hypoxia of the tissues and low blood pressure related to vasodilation. 

• Light pink to gray colored mucus membranes
• Tissue hypoxia 
• Ataxia 
• Weakness 
• Muscle tremors 
• Abnormally low body temperature 
• Weak heartbeat
• Polyuria (frequent urination)
• Anxiety
• Tachypnea (rapid breath) 
• Dyspnea (gasping for air) 
• Gastric hemorrhage
• Abdominal pain
• Diarrhea 
• Vomiting 
• Hypersalivation 
• Anorexia 
• Depression 
• Death 

Ambrosia Mexicana poisoning in cats is caused by consuming the leaves, stems, or seeds of the ambrosia plant. A feline can consume the plant directly by chewing on the leaves or indirectly by grooming, or ingesting soil containing the ambrosia seed. The toxic components of the Ambrosia Mexicana plant are cyanogenic glycosides, oxalates, and nitrates, which transforms to nitrite. The end result is nitrite poisoning as the lethal chemicals from the Ambrosia Mexicana plant are absorbed into the blood stream. 

The best way to diagnose an Ambrosia Mexicana poisoning in a cat is to witness the feline consuming the plant. If you do witness your cat licking, chewing or eating an Ambrosia Mexicana plant, take the plant with you to your cat’s veterinary appointment. If you have not witnessed plant consumption, the veterinarian will base his or her diagnosis on your cat’s presenting clinical signs. The diagnostic process will begin with a physical examination, review of the feline’s medical history and a consultation with the pet owner. Unfortunately, Ambrosia Mexicana nitrite poisoning symptoms mimic the symptoms of cyanide poisoning, so your veterinarian will need to conduct a diagnostic differential. The easiest way for a veterinarian to rule out cyanide poisoning is to take a sample of your cat’s blood. When a feline is suffering a cyanide toxicity, her/his blood will be a bright red, cherry color, whereas a nitrite toxicity will cause the feline’s blood to turn a dark brown, chocolate color. 

Ambrosia Mexicana poisoning is generally treated with methylene blue administered intravenously. Methylene blue works by reducing the ferric iron in hemoglobin (red blood cells) to the ferrous state. Therefore, this therapeutic agent converts methemoglobin cells that don’t carry oxygen into hemoglobin cells that will once again be receptive to oxygen transport.  The veterinarian may pair the use of Methylene blue with mineral oil. Used as a cathartic, mineral oil can aid in a faster defecation and speed up the removal of nitrate material from the feline’s gastrointestinal tract. The treatment series put in place by the veterinarian may be repeated as symptoms persist. 

If a diagnosis was promptly made and treatment was effective, a feline has a good chance of surviving an ambrosia Mexicana poisoning. However, if the clinical signs were not noticed until the lethal chemicals of the ambrosia plant were further absorbed, the feline’s chance for making a full recovery is guarded to poor. The best prevention method of nitrite toxicity in felines is to removal all Ambrosia Mexicana plants from your cat’s environment or keep the feline confined when you are not home.