The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.


Avoid with known allergy or sensitivity to Aloe vera, its parts, or plants of the Liliaceae family, such as garlic, onions, and tulips.

After prolonged use of an aloe gel applied to the skin, hives, allergic skin reactions, redness on the eyelids, and widespread skin inflammation have been reported.

Side Effects and Warnings

Aloe is likely safe when applied to the skin to reduce pain or inflammation. Aloe is likely safe for burns, frostbite, human papilloma virus-1 (HPV) infections (cold sores), psoriasis, and wound healing in people who are not allergic or sensitive to aloe. Medical attention should be sought for severe burns, wounds, or frostbite.

Aloe may lower blood sugar levels. Caution is advised in people with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Blood glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.

Aloe may increase the risk of bleeding. Caution is advised in people with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.

Use cautiously in people with heart disease or electrolyte abnormalities. Use cautiously when taken by mouth or used as a laxative.

Use cautiously in people taking agents for the heart, agents for the stomach or intestines, agents that increase potassium excretion, cardiac glycosides, oral corticosteroids, oral hydrocortisone, sevoflurane, thyroid hormones, topical hydrocortisone, or zidovudine (AZT).

Avoid in people with abdominal pain that is sudden and severe, appendicitis, bowel obstruction, fecal impaction, kidney disease, liver disease, or in people taking agents toxic to the liver. Avoid use as an injection, during postoperative incision healing, during pregnancy or lactation, or for prolonged periods as a laxative.

Avoid with known allergy or sensitivity to Aloe vera, its parts, or plants of the Liliaceae family, such as garlic, onions, and tulips.

Aloe may also cause abdominal cramping, allergic skin reaction, constipation, dehydration, dependency if used as a laxative, delayed wound healing, diarrhea, electrolyte imbalance, excess bleeding, hardening of the skin, Henoch-Schönlein purpura (purple spots on the skin), hepatitis, hives, increased risk of colorectal cancer, increased risk of irregular heartbeat, kidney failure, liver toxicity, low potassium in the blood, muscle weakness, redness of the skin and eyelids, skin dryness, skin inflammation from sun exposure, soreness, splitting of the skin, stinging, stomach discomfort, thyroid dysfunction, urinary stone, uterine contractions, and widespread inflammation of the skin.

Note: As a part of the Food and Drug Administration (FDA) over-the-counter (OTC) drug product review, a final rule was issued suggesting that the stimulant laxative ingredient of aloe (including aloe extract and aloe flower extract) in OTC products generally lack safety and effectiveness or may be misbranded.

Pregnancy and Breastfeeding

Although topical application is unlikely to be harmful during pregnancy or lactation, internal use is not suggested, due to theoretical stimulation of uterine contractions. It is not known if components of aloe may be excreted with breast milk. Consumption of the dried juice from aloe leaves is contraindicated during lactation.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration