Aloe Vera Leaves
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Despite your best efforts, your day in the sun took its toll and you now have a sunburn. The sun’s ultraviolet rays eventually overcame your sunblocker, causing that all too familiar red, painful sunburn. You may be thinking of using aloe vera gel, a remedy commonly used to reduce sunburn symptoms. Although this treatment has minimal side effects and is recommended by the American Academy of Dermatology, the effectiveness of aloe vera for sunburns has not been established by scientific research. Some indirect evidence from laboratory and animal research suggests that it can be beneficial, but there is almost no direct evidence from human studies demonstrating that aloe vera gel is effective for sunburns.

Long History of Use

Aloe vera is an herbal remedy that has been used for thousands of years for a variety of conditions, from skin problems to constipation to arthritis. It is derived from the Aloe vera plant, also called Aloe barbensis Miller. Aloe vera gel is the jelly-like substance from within the plant’s leaves and the main part of the plant, which is used for skin conditions.

A number of topical lotion, gel and spray aloe vera preparations are sold specifically for sunburns. Many sunburn products with aloe vera contain other ingredients as well, such as vitamins A, C, D, and E, oils, other herbs or a local anesthetic -- numbing medicine. These additional substances are purported to reduce sunburn symptoms or promote skin health. Homemade aloe vera gel can be made by simply cutting open a leaf and removing the clear gel inside.

Recommended by the American Academy of Dermatology

The American Academy of Dermatology (AAD) recommends using a moisturizer containing aloe vera or soy to reduce sunburn symptoms. However, AAD cautions against using any type of lotion containing a local anesthetic, such as benzocaine or lidocaine, as the anesthetic can cause skin irritation or an allergic reaction. Any preparation containing petrolatum should also be avoided because this waxy ingredient can trap heat within the skin, aggravating sunburn pain.

AAD suggests cool baths or showers and cold damp towels applied to the skin as additional sunburn treatments. The organization also indicates that anti-inflammatory medications, such as ibuprofen (Advil, Motrin) or aspirin, may help reduce pain and redness. Over-the-counter hydrocortisone cream may be helpful for relieving severe symptoms.

Minimal Direct Scientific Evidence

Despite its long history of use and AAD's recommendation, there is very little scientific evidence that aloe vera reduces sunburn symptoms or speeds healing. Few studies have directly evaluated these effects. A study published in the September 2005 issue of the "Journal of the Medical Association of Thailand" found treatment with 70 percent aloe vera cream for 3 weeks after exposure to ultraviolet radiation among 20 healthy volunteers was ineffective for sunburn treatment. Skin redness was the same in areas treated with aloe vera and those treated with a cream containing no active ingredients.

A subsequent study of 40 volunteers published in "Skin Pharmacology and Physiology" in February 2008 compared 97.5 percent aloe vera gel, 1 percent hydrocortisone gel and 1 percent hydrocortisone cream after exposure to a standardized amount of ultraviolet radiation. After 2 days, skin areas treated with aloe vera were less red than those treated with hydrocortisone gel, but redder than areas treated with hydrocortisone cream. These results suggest that high concentrations of aloe vera may exert some anti-inflammatory effects.

Limited Indirect Evidence

Laboratory and animal studies have demonstrated that topical aloe vera reduces inflammation and accelerates healing of wounds and thermal burns, which are those caused by excessive heat. These studies have also shown that aloe vera has antioxidant activity, allowing it to counteract the damaging effects of free radicals that accumulate in inflamed tissue. However, aloe vera's antioxidant effects have not been studied in humans. Some human studies have reported improved wound and thermal burn healing with aloe vera. But the number of high-quality studies conducted to date is insufficient to definitively prove that aloe vera improves healing, according to the authors of systematic reviews published in February 2012 in the "Cochrane Database of Systematic Reviews" and in September 2007 in the journal "Burns."

A small study published in the April-June 2014 issue of "Pharmacognosy Magazine" showed that aloe vera gel had some anti-inflammatory effects when skin was exposed to a liquid irritant. After 6 days of treatment with aloe vera gel, 1 percent hydrocortisone gel or water, the intensity of redness decreased by 17 percent with aloe vera, which was similar to the decrease seen with hydrocortisone but greater than the decrease seen with water. In a separate part of the study, aloe vera gel also improved skin hydration, although the effects were not sustained with repeated use.

Generally Minimal Side Effects

Topical aloe vera gel is generally safe, according to the National Center for Complementary and Integrative Health. Except for very rare severe allergic reactions, side effects are limited to the skin. Mild discomfort may occur at the site of application. Local skin reactions characterized by a rash, with or without itching or a stinging sensation, may also develop. These reactions may be more common with homemade aloe vera preparations that contain contaminants from the plant’s bark. Commercial aloe vera products usually do not contain these substances. In the 2014 "Pharmacognosy Magazine" study, 19 percent of people treated with aloe vera gel experienced a mild skin reaction.

Warnings and Precautions

Stop using aloe vera gel if you develop symptoms of a local skin reaction, such as increased redness, a rash or itchiness. Seek immediate medical care if you develop symptoms of a severe allergic reaction, such as a generalized rash or redness, swelling of the lips or tongue, shortness of breath, wheezing, lightheadedness or loss of consciousness.

A severe sunburn often causes blisters and swelling. When the sunburn involves a large area of the body, a fever, chills, weakness or even loss of consciousness can occur. Seek prompt medical attention if you have a severe sunburn over a large region, especially if you notice any of these additional symptoms. Blisters should be allowed to drain on their own and the area kept clean once this has happened. See your doctor if you notice any pus, or worsening redness or swelling in the blister area, as this may indicate an infection.

Reviewed by: Tina M. St. John, M.D.