Although generally considered safe when used topically, aloe vera capsules or juice taken orally can react with certain drugs. Aloe vera interactions with medications can reduce bioavailability, making drugs less effective, or increase the response that may trigger negative reactions and side effects.
Juice containing aloe vera may add variety to your beverage intake, but be aware that many of its beneficial health claims are unsubstantiated. Aloe vera juice is generally considered safe but can cause unhealthy outcomes if combined with some medications or other supplements.
What is Aloe Vera?
Aloe vera is a succulent plant — one of more than 400 species of the genus Aloe — originating in South Africa and belonging to the Liliaceae family, according to an article in the Journal of Traditional and Complementary Medicine published in December 2014. Many biological antibacterial and antimicrobial properties are associated with the pulp of the aloe leaves.
Aloe contains proteins, lipids, amino acids, vitamins, inorganic and small organic compounds, enzymes and various carbohydrates. Due to its potential healing attributes, the pulp of the aloe has traditionally been used to make a clear gel for topical use, or a yellow latex oral form, as a remedy for a wide range of clinical uses.
Topically, aloe is used for skin conditions such as burns, frostbite, psoriasis and cold sores. As a dietary supplement or juice, aloe vera may be used for osteoarthritis, bowel diseases, fever and constipation, according to National Center for Complementary and Integrative Health (NIH).
Read more: Aloe Vera Juice Storage Information
Reduced Bioavailability From Laxative Effect
Aloe vera juice is a potent laxative and is often used to cleanse the digestive system or relieve constipation. According to the National Institute of Environmental Health Sciences, the outer leaf pulp of aloe leaves used to make juice is made up of an organic component known as latex, which contains anthraquinones. Anthraquinones, such as aloin, give the plant its laxative qualities.
However, a review published in the Journal of Environmental Science and Health in January 2019 reported that aloe vera whole leaf extract showed evidence of carcinogenic activity in animals and was classified as a possible human carcinogen. Additionally, the long-term use of aloe vera juice as a laxative may interfere with the absorption of medications and nutrients, according to the January 2020 publication of Melanosis Coli.
Reports from the publication suggest that anthraquinones in aloe vera inhibit the reabsorption of water, sodium, potassium and any oral medication you may be taking in. The reduced transit time accelerates the gastrointestinal emptying, which means decreased bioavailability of medications and quick secretion with your feces. For this reason, aloe vera juice and antibiotics are not a good combination, nor are some heart and bone medications, says the Mayo Clinic.
Electrolyte Imbalance and Potassium Loss
Many people experience aloe vera side effects from using it as a laxative, which can include diarrhea and abdominal cramps. The Mayo Clinic warns that many oral laxatives may also lead to dehydration and the risk of an electrolyte imbalance, especially after prolonged use. Electrolytes including calcium, chloride, potassium, magnesium and sodium regulate many body functions.
An electrolyte imbalance can cause weakness, confusion, abnormal heart rhythms and seizures. Dangerously low levels of potassium can lead to fatigue, muscle weakness, irregular heartbeats and even hypokalemia.
To avoid serious potassium loss, do not drink aloe vera juice with diuretics such as thiazide, or heart medications such as digitalis, both of which are used to help remove excess fluid and lower potassium levels. In addition, an article in the Indian Journal of Dermatology published in July-August 2013 warns that combining aloe vera with prednisolone, used as an anti-inflammatory and immunosuppressant, can induce a loss of potassium in the body.
Read more: Aloe Vera Juice Side Effects
Aloe Vera Interactions With Medications
Many drugs you take orally can become less effective when combined with aloe vera juice. In some cases, aloe can reduce the bioavailability or block the action of the co-administered drug. In others, it can enhance the effect of the medication, triggering or worsening side effects of the drug.
Not only is aloe vera juice made from latex or whole-leaf extract likely to be unsafe in high doses, but also excessive intake for several days can cause acute kidney failure and can be fatal, according to the Mayo Clinic. Many drugs can be affected by combining them with supplements including aloe vera capsules and drinks made from the leaves of the plant.
Speak with your doctor if you intend to drink aloe vera juice and take any of the following drugs or supplements, in addition to the ones already mentioned:
- Anticoagulants and antiplatelet medications: These types of drugs, herbs and supplements
reduce blood clotting, as may oral use of aloe. If you drink aloe vera juice
with either of these types of medications, the result might be increased
bleeding, according to Mayo Clinic.
- Cardiac glycosides, such as digoxin and lanoxin: Since aloe latex can decrease potassium levels, low
potassium might increase the side effects of digoxin if you take aloe and
- Some anesthesias used during surgery, such as sevoflurane or ultane: These drugs are used to slow
blood clotting, but aloe vera taken orally might have a similar effect. If used
in combination, excessive bleeding during surgery is possible.
- Stimulant laxatives: Due
to the laxative effects of aloe vera, do not use in conjunction with other stimulant
laxative medications. Overstimulation of your bowels can lead to dehydration.
- Anticoagulants such as warfarin (coumadin, jantoven): Aloe vera can cause diarrhea and
increase the effects of warfarin, which is a blood-thinning drug. This
combination could increase the risk of bleeding.
- Diuretics, known as water pills: Drinking aloe vera juice in combination with the use of diuretics might decrease potassium levels too much and create a deficiency.
In addition to the risk of aloe vera interactions with medications, the use of aloe vera preparations should be avoided if you have an allergy to plants of the Liliaceae family (garlic, onions, and tulips).
- Journal of Traditional and Complementary Medicine: "Evaluation of Biological Properties and Clinical Effectiveness of Aloe Vera: A Systematic Review"
- NIH: National Center for Complementary and Integrative Health: "Aloe Vera"
- National Institute of Environmental Health Sciences: National Toxicology Program: "Aloe Vera"
- Journal of Environmental Science and Health: "Aloe vera: A Review of Toxicity and Adverse Clinical Effects"
- StatPearls [Internet]: Treasure Island (FL): "Melanosis Coli"
- Mayo Clinic: "Over-the-Counter Laxatives for Constipation: Use With Caution"
- U.S. Library of Medicine: "Digitalis Toxicity"
- Indian Journal of Dermatology: "Drug Interactions in Dermatology: What the Dermatologist Should Know"
- Mayo Clinic: "Aloe"