TL;DR: Aloe vera is toxic to cats because it contains saponins and anthraquinones that cause digestive upset. While usually not life-threatening, you should contact a vet if your cat shows signs like vomiting, diarrhea, or lethargy.
What makes aloe vera toxic to cats?
While aloe vera is known for its healing properties in humans, it contains compounds called saponins and anthraquinones that are toxic to cats. When a cat chews on the leaves, they often ingest the latex layer—a bitter, yellowish sap—which acts as a potent laxative and irritant to their digestive system.
Is it an emergency if my cat eats aloe vera?
- The urgency level for aloe vera ingestion is typically Medium and rarely life-threatening.
- Ingestion can cause significant discomfort, including vomiting, diarrhea, lethargy, and a change in urine color.
- You should monitor your cat closely and contact your veterinarian, especially if they are unable to keep food or water down or appear exceptionally weak.
How does a photo of the plant help my veterinarian with triage?
- A photo helps confirm the specific species of aloe to ensure accurate identification.
- It allows the professional to see the extent of the damage to the leaves, which helps estimate the amount of toxin ingested.
- If your cat has vomited, a photo of the contents can help the vet determine the severity of the gastrointestinal irritation.
Clinical Context (Merck Veterinary Manual)
Aloe vera ingestion in cats can cause local irritation to mucous membranes, excess salivation, swollen tongue and pharynx, diarrhea, and dyspnea. The plant contains anthraquinone glycosides (barbaloin, emodin) and chrysophanic acid in the latex of the leaves, with higher concentrations in younger leaves, leading to abrupt, severe diarrhea and/or hypoglycemia, with vomiting in some cases. Treatment is symptomatic, focused on controlling diarrhea and fluid loss, assessing dehydration and electrolyte status, and providing electrolyte replacement therapy in severe cases. Analgesics and/or demulcents may be indicated for burning/painful/inflammatory reactions in the mouth.
Chapter: Toxicology
Source: The Merck Veterinary Manual, 11th Edition (Page 3105)