Aloe barbadensis
Aloaceae
Barbados Aloe; True Aloe; Medicine Plant; Aloe; Aloe Vera; Aloe barbadensis; Aloe barbadensis miller; Aloe vera
Anthraquinone glycosides and anthracene glycosides, including barbaloin/aloin and emodin; saponins; chrysophanic acid and other irritating compounds concentrated primarily in the yellow latex of the leaves, with higher concentrations reported in younger leaves.
Vomiting, diarrhea, accelerated defecation, abdominal discomfort, lethargy, depression, tremors, change in urine color including dark brown or reddish urine, and possible contact dermatitis or irritation of the mouth, throat, nose, face, or other exposed skin. Severe diarrhea may place the pet at risk for dehydration and electrolyte imbalance.
Although Aloe is generally considered a healing plant or herbal remedy, it can be harmful to pets if ingested. Aloe barbadensis, commonly known as Barbados Aloe, True Aloe, Medicine Plant, or Aloe Vera, is widely kept as a houseplant and is commonly associated with burns, skin irritation, topical gels, and traditional herbal use. This reputation can make the plant seem harmless, but the risk to pets depends heavily on which part of the leaf is consumed.
The clear inner gel of the Aloe leaf is generally considered the safer portion of the plant and is the portion most commonly associated with topical human use. The primary concern for pets is the yellowish, bitter Aloe latex, sometimes referred to as Aloe juice, which is found just under the skin or rind of the leaf. This latex contains aloin and related anthraquinone glycosides that act as powerful laxative compounds. ASPCA identifies True Aloe, Medicine Plant, and Barbados Aloe as toxic to dogs and cats, listing anthraquinones, anthracene glycosides, and aloin as the toxic principles, with clinical signs including vomiting and a red change in urine color.
Once ingested, aloin increases symmetrical contraction and relaxation of the muscles of the colon, thereby inducing bowel movements. Aloin also opens chloride channels of the colonic membrane, preventing the colon from reabsorbing water from the gastrointestinal tract and leading to softer stools. Aloe latex also has an irritative effect on the large intestines, and when that irritation is combined with its properties as a natural laxative, it can lead to significant diarrhea and place the pet at risk for dehydration.
The University of Wisconsin has likewise identified Aloe Vera as a toxic plant, noting that consumption of large amounts of Aloe Vera latex has caused diarrhea severe enough to result in dehydration and electrolyte imbalance. This is the primary practical concern in companion animals: not that every ingestion will be life-threatening, but that vomiting and diarrhea can become severe enough to create secondary complications, particularly in small animals, young animals, elderly pets, or animals with existing medical problems.
There is also the possibility of contact dermatitis or irritation of the mouth, throat, nose, face, and other exposed skin in animals with sensitive skin or latex-type sensitivities. A pet that chews the leaf may be exposed not only to the laxative compounds in the latex, but also to bitter, irritating plant material that can produce drooling, mouth discomfort, facial irritation, or reluctance to eat or drink.
The ingestion of Aloe by a pet is generally not considered likely to be life-threatening in most ordinary household exposures, and symptoms will typically be limited to mild to severe gastrointestinal upset, including vomiting and diarrhea, a change in urine color, lethargy, depression, and possible tremors. However, because aloin can potentially cause uterine contractions, pregnant animals should not be allowed access to areas containing Aloe plants.
Immediate Response to Aloe Ingestion or Contact
- Remove the Source: Prevent further ingestion by removing the Aloe plant, broken leaves, chewed leaf pieces, exposed latex, gel, or any remaining plant material from the pet’s reach.
- Identify the Part Ingested: Determine whether the pet chewed the outer leaf, swallowed the yellow latex, ingested the clear inner gel, or consumed a prepared Aloe product, because the yellow latex just under the leaf skin is the primary concern.
- Flush Contact Areas: If contact dermatitis, oral irritation, facial irritation, or skin exposure is noted, flush the affected area thoroughly with water to remove bitter latex or irritating plant residue.
- Monitor for Gastrointestinal Signs: Watch for vomiting, diarrhea, accelerated defecation, abdominal discomfort, drooling, lethargy, depression, tremors, or a dark brown to reddish change in urine color.
- Contact Veterinary Help: Consult a veterinarian, emergency veterinary clinic, ASPCA Animal Poison Control, or Pet Poison Helpline if a large amount was ingested, if symptoms are present, if diarrhea is severe, if urine color changes, if tremors occur, or if the pet is pregnant, very small, elderly, young, or medically fragile.
Inducing Vomiting and Decontamination
- Spontaneous Vomiting May Occur: In many cases, the pet may vomit naturally after swallowing bitter, irritating, non-digestible plant material.
- Inducing Vomiting in Dogs Only: If ingestion was recent and the dog is alert, breathing normally, able to swallow, and not showing weakness, collapse, tremors, repeated vomiting, severe depression, bloody diarrhea, or breathing difficulty, a veterinarian or animal poison-control professional may recommend inducing vomiting with fresh 3% hydrogen peroxide.
- Cat Warning: Hydrogen peroxide should not be used to induce vomiting in cats unless a veterinarian specifically directs it. Cats are more prone to irritation and complications from hydrogen peroxide, and home vomiting attempts may create more risk than benefit.
- Do Not Induce Vomiting in an Unstable Animal: Vomiting should not be attempted in any animal that is weak, collapsed, sedated, having trouble breathing, unable to swallow normally, repeatedly vomiting, showing neurologic signs, or already suffering severe diarrhea or dehydration.
- Veterinary Decontamination: If decontamination is appropriate, a veterinarian may induce vomiting, administer activated charcoal, provide anti-nausea medication, or recommend other supportive care depending on the amount ingested, timing, species, and clinical signs.
Symptomatic Care and Treatment
- Hydration: Ensure the pet receives adequate fluids to reduce the risk of dehydration caused by diarrhea, vomiting, or accelerated bowel movements.
- Dehydration Risk: If the pet is severely dehydrated, weak, unable to keep water down, or experiencing persistent diarrhea, veterinary care and intravenous fluid therapy may be required.
- Electrolyte Concerns: Severe diarrhea may lead to electrolyte imbalance, especially in small pets, puppies, kittens, elderly animals, pregnant animals, or pets with existing illness.
- Gastrointestinal Protection:
- Kapectolin: To alleviate gastrointestinal upset and diarrhea, Kapectolin may be given at a dose of 1 to 2 ml/kg four times daily to help coat and protect the stomach lining.
- Sucralfate: Sucralfate may be used for gastrointestinal irritation because it reacts with stomach acid to form a paste-like protective barrier between irritated tissue and stomach contents.
- Dogs greater than 60 lbs: 1g every 6 to 8 hours.
- Dogs less than 60 lbs: 0.5g every 6 to 8 hours.
- Cats: 0.25g every 8 to 12 hours.
Prognosis and Recovery
- General Outlook: The prognosis with symptomatic and supportive treatment is generally good, and most pets are expected to recover fully.
- Expected Recovery: Pets with uncomplicated Aloe ingestion are typically expected to make a full recovery within 1 to 2 days.
- Higher-Risk Cases: Veterinary care is recommended when diarrhea is severe or persistent, dehydration is present, tremors occur, urine becomes dark brown or reddish, the pet is pregnant, or the pet becomes weak, depressed, or unable to keep fluids down.
- Prevention: Pregnant animals and pets prone to chewing houseplants should not be allowed access to Aloe plants, especially broken leaves where the bitter yellow latex is exposed.