From the Guidelines
Yes, it is possible to overdose on aloe vera when consumed orally in large amounts. Aloe vera gel is generally safe for topical use, but ingesting excessive amounts of aloe latex (the yellow substance just under the plant's skin) can cause serious health problems. Symptoms of aloe vera overdose include severe abdominal cramps, diarrhea, dehydration, electrolyte imbalances, and kidney damage. The anthraquinones in aloe latex act as strong laxatives and can be harmful in high doses.
Key Considerations
- The risk of contact dermatitis is present in patients who use Aloe vera, as noted in the joint AAD-NPF guidelines of care for the management and treatment of psoriasis with topical therapy and alternative medicine modalities for psoriasis severity measures 1.
- For those who wish to consume aloe vera internally, it's recommended to use only specially prepared food-grade aloe products and follow package directions carefully.
- People with certain medical conditions (kidney disease, heart disease, diabetes, intestinal disorders) should consult a healthcare provider before consuming aloe vera.
- Pregnant women and children should generally avoid oral aloe products.
Important Warnings
- If you experience symptoms of overdose after consuming aloe vera, seek medical attention immediately.
- Treatment should not be used in patients who are allergic to Aloe vera, as stated in the guidelines 1.
- The benefits and risks of using Aloe vera should be carefully considered, especially in patients with a history of skin cancer and/or continued heavy sun exposure, including phototherapy.
From the Research
Aloe Vera Overdose
- Ingestion of Aloe preparations is associated with several adverse effects, including diarrhea, hypokalemia, pseudomelanosis coli, kidney failure, as well as phototoxicity and hypersensitive reactions 2.
- A study on the safety evaluation of Aloe vera soft capsule found no mortality or behavioral changes in mice receiving a high dose of 15000 mg/kg bodyweight, indicating a low risk of acute toxicity 3.
- However, another study found that Aloe vera whole leaf extract showed clear evidence of carcinogenic activity in rats, and was classified as a possible human carcinogen (Group 2B) by the International Agency for Research on Cancer 2.
Toxicity and Adverse Effects
- The toxicological effects of Aloe vera include cytotoxicity, genotoxicity, carcinogenicity, and adverse clinical effects, which are associated with the presence of anthraquinones, such as aloin 2.
- A 90-day repeated dose oral toxicity study of an Aloe vera inner leaf gel beverage found no adverse test substance-related findings, including altered thyroid hormones, and no histologic differences or histopathological changes were detected in multiple tissues and organs examined 4.
- Topical application of Aloe vera is not an effective preventative for radiation-induced injuries, but it might be effective for genital herpes and psoriasis, although the clinical effectiveness of oral or topical Aloe vera is not sufficiently defined at present 5.
Safety Evaluation
- The safety evaluation of Aloe vera products is important due to the reported adverse effects, and studies have aimed to assess the toxicological profile of Aloe vera through acute, subacute toxicity, and genotoxicity tests 3.
- A study found that Aloe vera soft capsule did not produce any marked subacute toxic effects up to a maximum concentration of 3330 mg/kg bodyweight, and showed no mutagenic activity in the Ames test 3.
- The safety of appropriately processed Aloe vera gel beverages has been evaluated, and the data lend increasing confidence regarding their safety, although more research is needed to fully understand the potential risks and benefits of Aloe vera consumption 4.