Herbal Monograph
Aloe vera
Aloe barbadensis Mill.
Asphodelaceae (formerly Xanthorrhoeaceae, Aloaceae, Liliaceae)
Cooling, soothing succulent renowned for burn healing, wound care, and digestive support — with a critical...
Overview
Plant Description
Aloe barbadensis is a succulent, evergreen perennial plant forming dense rosettes of thick, fleshy, lance-shaped leaves arising from a very short stem or near-acaulescent base. The leaves are 30-60 cm (12-24 inches) long and 5-8 cm (2-3 inches) wide at the base, tapering to a point, with a concave upper surface and convex lower surface. The leaf margins bear small, pale, cartilaginous teeth (serrations) spaced 10-20 mm apart. Leaf color is grey-green to bright green, sometimes with faint whitish spots or mottling on younger leaves that fade with maturity. The leaf epidermis is thick and waxy (cuticle). Beneath the epidermis lies a layer of pericyclic tubules (specialized cells in the vascular bundle sheath) that produce and contain the yellow, bitter latex (also called aloe juice or sap). The interior of the leaf is filled with a thick, colorless, mucilaginous gel (parenchyma tissue) that constitutes the commercially important 'aloe vera gel.' This structural distinction between the outer latex layer and inner gel is fundamental to understanding the plant's medicinal uses and safety profile. The inflorescence is a dense, cylindrical raceme on a simple or branched scape 60-90 cm tall, bearing pendulous, tubular, yellow flowers 2.5-3 cm long. The plant propagates vegetatively by producing lateral offshoots (pups) from the base, and also by seed. Root system is shallow and fibrous.
Habitat
Aloe barbadensis is adapted to warm, arid, and semi-arid climates. It grows naturally in dry, rocky, well-drained soils and thrives in full sun with minimal rainfall. The plant is extremely drought-tolerant due to its succulent water-storage capacity (CAM photosynthesis). It is frost-sensitive and cannot tolerate prolonged temperatures below 0 degrees C. In cultivation, it grows well in sandy or gravelly, well-drained soils with moderate fertility. It is commonly found wild or naturalized in Mediterranean-climate regions, tropical and subtropical coastal areas, and arid grasslands.
Distribution
The precise native range of Aloe barbadensis is debated but is generally considered to be the Arabian Peninsula (particularly the Dhofar region of Oman and western Yemen), with possible early distribution to northeastern Africa (Sudan, Ethiopia). The plant was distributed throughout the Mediterranean, North Africa, and the Indian subcontinent in antiquity through trade routes, and was introduced to the Caribbean (Barbados, Curaçao — hence the common names), Central America, and other tropical regions during the colonial era. Today it is cultivated commercially on a massive scale worldwide, with major production in Mexico, the Dominican Republic, China, India, Thailand, Australia, the southern United States (Texas), and various Caribbean and Central American countries. It is naturalized throughout much of the tropics and subtropics globally. Global annual production of aloe vera gel exceeds 60,000 tonnes.
Parts Used
Inner leaf gel (Aloe vera gel, Aloe barbadensis leaf juice)
Preferred: Fresh inner leaf gel for topical application; stabilized commercial gel for topical or oral use; freeze-dried or spray-dried gel powder (standardized to acemannan/polysaccharide content) for capsules and supplements
The colorless, mucilaginous parenchymal gel from the inner leaf, carefully separated from the outer rind and latex layer. This is the most widely used aloe preparation globally and the basis for the vast majority of commercial aloe vera products (drinks, topical gels, cosmetics). The gel is composed of approximately 99% water and 1% solids, with the polysaccharide acemannan as the primary bioactive constituent. The gel has a fundamentally different composition and safety profile from the latex — it is essentially free of anthraquinone glycosides when properly processed. Classified AHPA Safety Class 1 (safe when used appropriately). The gel is the basis for the WHO monograph on 'Aloe Vera Gel' (distinct from the WHO monograph on 'Aloe' which covers the latex).
Latex (Aloe, Aloes, Aloe barbadensis leaf latex, dried juice)
Preferred: Dried latex (drug aloes) standardized to hydroxyanthracene derivative content; capsules or tablets of dried latex standardized to 20-30 mg hydroxyanthracene derivatives per dose (calculated as aloin)
The bitter, yellow exudate produced by pericyclic tubules located between the outer leaf rind and the inner gel parenchyma. Contains 25-40% anthraquinone glycosides (primarily aloin A and B / barbaloin). This is the traditional 'drug aloes' of pharmacopeias worldwide — a potent stimulant laxative with a fundamentally different use, dosage, and safety profile from the gel. Listed in virtually all major pharmacopeias (Commission E, WHO, EMA, BHP, USP) specifically as a stimulant laxative. AHPA Safety Class 2b (not to be used during pregnancy) and 2c (not to be used while nursing). The latex is obtained by cutting the leaf and collecting the draining exudate, which is then concentrated by evaporation. It should NOT be confused with aloe vera gel products.
Whole leaf extract (decolorized or non-decolorized)
Preferred: Decolorized whole leaf extract powder or juice (variable quality; check for anthraquinone content specification)
Prepared from the entire leaf including rind, latex, and gel, processed together. Non-decolorized whole leaf extract contains anthraquinones and has laxative properties similar to the latex. Decolorized whole leaf extract has been charcoal-filtered to remove most (but potentially not all) anthraquinones, producing a product intermediate between gel and latex in composition. The International Aloe Science Council (IASC) distinguishes between 'inner leaf' (gel) and 'whole leaf' products. Decolorized whole leaf aloe extract was the subject of a 2-year NTP carcinogenicity study in rodents (2013) that found increased incidence of intestinal tumors — though the relevance to purified gel products and to humans is debated. Products labeled 'whole leaf' should be used with awareness of potential anthraquinone content.
Key Constituents
Polysaccharides (acemannan and related glucomannans)
Polysaccharides, particularly acemannan, are the primary bioactive constituents of the gel responsible for wound healing, immunomodulation, anti-inflammatory, and gastroprotective effects. Acemannan's immunomodulatory activity (macrophage activation, cytokine induction) provides the mechanistic basis for enhanced wound healing, anti-inflammatory effects, and potential anti-tumor adjunctive activity. The polysaccharide content and integrity are the most important quality parameters for aloe vera gel products — degradation during processing (heat, enzymes, oxidation) reduces biological activity. Acemannan is water-soluble and present only in the gel, not significantly in the latex.
Anthraquinone glycosides (hydroxyanthracene derivatives)
Anthraquinone glycosides are the active laxative constituents of aloe LATEX specifically — they are NOT significant constituents of properly processed aloe vera GEL. The stimulant laxative action (Commission E approved, WHO-listed, EMA well-established traditional use) is well-documented but restricted to short-term use (1-2 weeks maximum) due to concerns about electrolyte depletion, dependency, and the potential long-term carcinogenicity signal from animal studies. The clear separation of anthraquinone-containing latex from anthraquinone-free gel is the single most important quality control issue in the aloe industry and the foundation of the dramatically different safety profiles of these two preparations.
Vitamins
Vitamins contribute modestly to the antioxidant and nutritional profile of aloe vera gel but are not considered primary active constituents at the concentrations present. The vitamin content is sometimes emphasized in marketing but is of minor therapeutic significance compared to the polysaccharide and enzyme components.
Enzymes
Enzymes, particularly bradykinase and the antioxidant enzymes (SOD, catalase), contribute to the anti-inflammatory and wound-healing properties of fresh aloe vera gel. Bradykinase-mediated degradation of bradykinin provides a direct anti-inflammatory mechanism. These enzymes are most active in fresh or minimally processed gel and may be substantially inactivated by pasteurization and prolonged storage, which is one reason fresh aloe gel is traditionally preferred for topical wound care.
Organic acids and phenolic compounds
Salicylic acid is a therapeutically significant minor constituent, providing direct anti-inflammatory and analgesic effects that complement the polysaccharide-mediated anti-inflammatory activity. The presence of endogenous salicylic acid in aloe gel contributes to the well-documented soothing and pain-relieving effects on burns and minor wounds.
Sterols and fatty acids
Phytosterols (particularly lupeol and beta-sitosterol) contribute to anti-inflammatory activity and provide mild analgesic effects. The fatty acid content is minor but the presence of GLA as a PGE1 precursor may contribute to anti-inflammatory balance. The combined sterol-fatty acid fraction contributes to the overall anti-inflammatory and wound-healing profile of aloe gel.
Minerals and trace elements
Minerals contribute modestly to the overall therapeutic profile. Zinc supports wound healing and immune function. Chromium may contribute to insulin-sensitizing and glucose-regulating effects observed in clinical studies of oral aloe vera for type 2 diabetes. However, mineral concentrations in typical aloe doses are nutritionally modest.
Amino acids and glycoproteins
Glycoproteins (particularly aloctin A) contribute to anti-inflammatory and immunomodulatory activity. Aloctin A's inhibition of histamine release provides an anti-allergic mechanism complementary to other anti-inflammatory constituents. Free amino acids are of minor individual significance but contribute to the overall nutritive quality of the gel.
Herbal Actions
Promotes wound healing
The hallmark therapeutic action of aloe vera gel. Multiple systematic reviews and meta-analyses confirm that topical aloe vera gel accelerates wound healing, particularly for first- and second-degree burns. Maenthaisong et al. (2007) meta-analysis of 4 controlled trials found healing time was reduced by a mean of 8.79 days compared to controls. A 2024 systematic review and meta-analysis of 9 RCTs (Zheng et al. 2024) confirmed that aloe vera significantly reduced mean wound-healing time by 3.76 days in second-degree burns. Mechanisms include: acemannan-mediated macrophage activation and growth factor release (VEGF, FGF, TGF-beta), fibroblast proliferation and collagen synthesis stimulation, anti-inflammatory reduction of wound-bed inflammation, increased tissue oxygenation, and maintenance of moist wound environment. The WHO monograph on Aloe Vera Gel supports topical use for burns and wound healing.
[1, 4, 7, 8, 10]Soothes and protects irritated mucous membranes
The high polysaccharide content (particularly acemannan) gives aloe vera gel pronounced demulcent (soothing, coating) properties when applied topically to skin and mucous membranes or when consumed orally. The mucilaginous gel forms a protective, hydrating film over irritated tissue surfaces, reducing friction and contact with irritants. This demulcent action contributes to its therapeutic benefit in GERD (coating the esophageal mucosa), peptic ulcer disease (protecting the gastric mucosa), oral mucositis (coating the oral mucosa), and various dermatological conditions. David Hoffmann (2003) classifies aloe gel as a demulcent vulnerary for both topical and internal use.
[1, 4, 5]Topically, aloe vera gel softens, soothes, and hydrates the skin. The gel's high water content, polysaccharides, amino acids, and lipid fraction contribute to skin moisturization and barrier function improvement. Clinical studies confirm its efficacy as an emollient in various dermatological conditions including xerosis (dry skin), radiation dermatitis, and psoriasis. The emollient action is enhanced by the gel's slightly acidic pH (4.5-5.5), which is compatible with the skin's natural acid mantle.
[1, 4]Reduces inflammation
Aloe vera gel demonstrates significant anti-inflammatory activity through multiple complementary mechanisms: (1) Bradykinase enzyme degrades bradykinin, a key inflammatory mediator. (2) Salicylic acid inhibits cyclooxygenase (COX), reducing prostaglandin synthesis. (3) Phytosterols (lupeol, beta-sitosterol) provide steroidal anti-inflammatory effects. (4) Acemannan modulates macrophage cytokine production. (5) Aloctin A inhibits histamine release from mast cells. (6) Magnesium lactate inhibits histamine release. The multi-target anti-inflammatory mechanism distinguishes aloe from single-agent anti-inflammatory drugs. Both topical and oral anti-inflammatory effects are documented.
[1, 4, 5, 10]LATEX ONLY — not the gel. Aloe latex is a potent stimulant (anthranoid) laxative, approved by the German Commission E and listed in the WHO, EMA, BHP, and major pharmacopeias for short-term treatment of occasional constipation. The anthraquinone glycosides (aloin A/B) are hydrolyzed by colonic bacteria to aloe-emodin anthrone, which stimulates colonic peristalsis and inhibits water and electrolyte reabsorption. Effect onset is 6-12 hours after oral ingestion. Commission E recommends a dose providing 20-30 mg hydroxyanthracene derivatives (calculated as aloin) per day. Use limited to 1-2 weeks maximum to avoid electrolyte disturbance and dependency. This action does NOT apply to properly processed aloe vera gel.
[1, 2, 3, 4, 5]Modulates and balances immune function
Acemannan and aloeride polysaccharides activate innate immune cells via mannose receptors and Toll-like receptors on macrophages and dendritic cells. In vitro and animal studies demonstrate enhanced macrophage phagocytosis, nitric oxide production, and cytokine release (IL-1, IL-6, TNF-alpha, IFN-gamma). Enhanced NK cell activity and T-cell proliferation have been observed. Acemannan has been used as a veterinary immunostimulant (Acemannan Immunostimulant, licensed for fibrosarcoma in cats and dogs). Human clinical evidence for systemic immunomodulation is preliminary, with most evidence derived from in vitro and animal models.
[1, 5]Kills or inhibits the growth of microorganisms
Aloe vera gel and its constituents demonstrate broad-spectrum antimicrobial activity in vitro against both gram-positive and gram-negative bacteria (including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli), fungi (Candida albicans), and some viruses (HSV-1, HSV-2 in vitro). Anthraquinones (from the latex) show stronger antimicrobial activity than gel constituents alone. Acemannan has demonstrated antiviral activity against enveloped viruses in vitro, and has been investigated as an adjunctive in HIV/AIDS management (early studies, not confirmed in large trials). The antimicrobial activity of the gel contributes to its wound-healing efficacy by helping prevent wound infection.
[1, 10]Multiple clinical studies and meta-analyses support a modest blood glucose-lowering effect of oral aloe vera preparations in prediabetes and type 2 diabetes. Dick et al. (2016) meta-analysis of 9 studies found significant reduction in fasting blood glucose (mean -46.6 mg/dL) and HbA1c (mean -1.05%). Suksomboon et al. (2016) meta-analysis of 8 RCTs confirmed improvements in fasting glucose and HbA1c. Mechanisms are not fully elucidated but may include enhanced insulin sensitivity, chromium-mediated insulin signaling enhancement, alpha-glucosidase inhibition, and modulation of hepatic glucose metabolism. Effects are modest and not a substitute for standard diabetes management.
[5, 16, 17]Stimulates bile flow from the gallbladder
Aloe latex, due to its bitter anthraquinone content, has been traditionally used as a bitter digestive stimulant and cholagogue (bile flow promoter). The intensely bitter taste stimulates the bitter reflex pathway, promoting gastric and biliary secretion. This cholagogue action is specific to the latex and is associated with its anthraquinone content. Hoffmann (2003) notes the cholagogue action as a secondary property of aloe latex preparations.
[4, 5]Stimulates digestive secretions via bitter taste receptors
LATEX ONLY. The anthraquinone glycosides in aloe latex produce an intensely bitter taste. In Western herbal energetics and in Ayurvedic medicine (tikta rasa), the bitter quality supports digestive secretion, liver function, and intestinal peristalsis. The gel itself is relatively bland, with only a slightly bitter and sweet taste.
[4, 5]Therapeutic Indications
dermatological
Burns (first- and second-degree, including sunburn)
The best-established clinical indication for aloe vera gel. Multiple systematic reviews and meta-analyses confirm efficacy. Maenthaisong et al. (2007) systematic review of 4 controlled trials (n=371) found mean healing time reduction of 8.79 days vs. controls (P=0.006). Sharma et al. (2022) meta-analysis found healing time reduced by 4.44 days (P=0.004). Zheng et al. (2024) meta-analysis of 9 RCTs confirmed significant reduction in wound-healing time for second-degree burns (mean difference -3.76 days) without increased infection risk. WHO monograph on Aloe Vera Gel supports this indication. The gel is applied topically to the burn surface after initial cooling, providing a moist healing environment, anti-inflammatory activity, and growth factor stimulation. Most effective for partial-thickness (first- and second-degree) thermal burns. Not a substitute for professional burn care for extensive or deep burns.
[1, 4, 7, 8, 9, 10]Wound healing (general, minor cuts, abrasions, surgical wounds)
Hashemi et al. (2015) systematic review of 23 clinical trials confirmed aloe vera use across wound types including surgical wounds, pressure ulcers, and cracked nipples. Acemannan-mediated macrophage activation promotes growth factor release and fibroblast proliferation. Anti-inflammatory and antimicrobial properties support wound bed preparation. Clinical evidence is strongest for superficial wounds; deep or complex wounds require standard surgical management.
[1, 4, 22]Psoriasis vulgaris (mild to moderate plaque psoriasis)
Syed et al. (1996) double-blind, placebo-controlled trial (n=60) of topical 0.5% aloe vera extract cream found 83.3% cure rate in the aloe group vs. 6.6% with placebo (P<0.001), with significant PASI score reduction. However, a subsequent study (Paulsen et al. 2005) using a commercial aloe gel found no significant benefit over placebo in mild-to-moderate psoriasis, suggesting formulation and concentration are critical variables. WHO monograph notes the traditional use of aloe for psoriasis. Evidence is mixed; the strongly positive Syed result has not been consistently replicated. May be useful as adjunctive therapy.
[1, 10, 11, 12]Radiation dermatitis (prevention and treatment)
Used clinically to prevent and treat radiation-induced skin reactions in cancer patients undergoing radiotherapy. Results from controlled trials are mixed — some show benefit in reducing severity of acute radiation dermatitis, while others show no significant advantage over standard skin care. A 2013 systematic review by Richardson et al. concluded that evidence was insufficient to recommend aloe vera for radiation dermatitis prevention, though some individual trials were positive. It remains widely used in clinical practice as a soothing topical agent during radiotherapy.
[1, 10]Atopic dermatitis and eczema (adjunctive)
Traditional use of aloe gel for soothing inflamed, itchy skin in eczema and dermatitis. The anti-inflammatory, emollient, and skin-barrier-supporting properties provide a rational basis. Limited controlled clinical trial data specifically for atopic dermatitis. Used as a complementary topical alongside standard dermatological management.
[1, 4]Genital herpes (topical treatment of lesions)
Syed et al. (1997) conducted a double-blind, placebo-controlled RCT of 0.5% aloe vera extract cream in men with first episodes of genital herpes (n=120). The aloe cream significantly shortened mean healing time compared to both placebo cream and placebo gel (4.8 days vs. 7.9 and 14.0 days, respectively, P<0.001). Response rate was 67% in the aloe group vs. 7% in placebo. Acemannan's in vitro antiviral activity against HSV and the gel's wound-healing properties contribute to efficacy. This is an area warranting further confirmatory research.
[10, 13]gastrointestinal
Constipation (short-term, occasional)
LATEX ONLY. The best-established and most extensively documented pharmacopeial indication for aloe latex. German Commission E positive monograph (1993) approved aloe (latex) for short-term treatment of constipation. WHO monograph on Aloe (Vol. 1, 1999) supports this indication. EMA monograph classifies it as a well-established traditional use. The anthraquinone glycosides (aloin A/B) are converted by colonic bacteria to aloe-emodin anthrone, which stimulates colonic peristalsis and inhibits water reabsorption, producing a soft to semi-liquid stool in 6-12 hours. Commission E dosage: the smallest effective dose, providing 20-30 mg hydroxyanthracene derivatives per day (calculated as aloin). STRICTLY limited to 1-2 weeks continuous use. Not for chronic constipation management. Contraindicated in intestinal obstruction, acute inflammatory bowel disease, appendicitis, abdominal pain of unknown origin, and in children under 12.
[1, 2, 3, 4, 5]Gastroesophageal reflux disease (GERD)
Panahi et al. (2015) published a randomized trial comparing aloe vera syrup (10 mL/day) with omeprazole and ranitidine in patients with GERD. Aloe vera was found to be safe, well-tolerated, and reduced all assessed GERD symptoms (heartburn, food regurgitation, flatulence, belching, dysphagia, nausea, vomiting) to a comparable degree as the pharmaceutical comparators at weeks 2 and 4. The demulcent, anti-inflammatory, and gastroprotective properties of aloe gel polysaccharides provide a rational mechanism. This is a single study requiring replication.
[4, 15]Irritable bowel syndrome (IBS)
Davis et al. (2006) conducted an RCT of oral aloe vera gel in IBS patients and found no significant benefit over placebo for IBS symptom composite scores, though there was a possible benefit in diarrhea-predominant IBS patients. Khedmat et al. (2013) found aloe vera decreased IBS pain and flatulence scores. Evidence is mixed and insufficient for a firm recommendation. The demulcent and anti-inflammatory properties of the gel provide theoretical support, while the laxative latex would be contraindicated in diarrhea-predominant IBS.
[5, 10]Peptic ulcer disease (adjunctive gastroprotection)
Traditional use in Western herbalism and Ayurveda for soothing gastric and duodenal ulceration. The demulcent polysaccharide gel forms a protective coating over the ulcer crater, and the anti-inflammatory and wound-healing properties support mucosal repair. Acemannan has shown gastroprotective effects in animal models of ethanol- and indomethacin-induced gastric ulceration. Limited controlled clinical trial data. Hoffmann (2003) lists aloe gel among demulcent herbs for gastritis and peptic ulcer.
[4, 5]Inflammatory bowel disease (ulcerative colitis — adjunctive)
Langmead et al. (2004) conducted a double-blind RCT of oral aloe vera gel (100 mL twice daily for 4 weeks) in patients with mild to moderate active ulcerative colitis (n=44). Clinical remission occurred in 30% of aloe patients vs. 7% placebo (not statistically significant due to small sample), and Simple Clinical Colitis Activity Index (SCCAI) scores decreased significantly more with aloe (P=0.01). Histological scores also improved. This small but well-designed study provides preliminary support. NOTE: Aloe LATEX is contraindicated in active UC and Crohn's disease due to its irritant cathartic properties.
[5, 14]oral-mucosal
Oral mucositis (radiation- and chemotherapy-induced)
Multiple RCTs support the use of aloe vera mouthwash/gel for prevention and treatment of cancer treatment-induced oral mucositis. A 2025 systematic review and meta-analysis (Wang et al.) of RCTs confirmed that aloe vera significantly reduces oral mucositis severity and duration in patients undergoing radiotherapy or chemotherapy. Su et al. (2004) RCT found aloe vera gel reduced the severity of radiation-induced mucositis. Mansouri et al. (2016) triple-blind RCT found aloe mouthwash comparable to benzydamine for radiation-induced oral mucositis. The demulcent, anti-inflammatory, and wound-healing properties of aloe vera gel provide a strong mechanistic basis for this application.
[5, 19, 20]Oral lichen planus
Choonhakarn et al. (2008) conducted an RCT of topical aloe vera gel vs. triamcinolone acetonide for oral lichen planus (n=54) and found aloe vera gel was significantly effective in improving clinical scores and symptoms, with response comparable to the corticosteroid. Salazar-Sanchez et al. (2010) confirmed improvement in oral lichen planus with topical aloe vera. The anti-inflammatory, immunomodulatory, and wound-healing properties of the gel support this application for an often treatment-resistant condition.
[10, 21]Aphthous stomatitis (canker sores)
Small clinical studies suggest topical aloe vera gel accelerates healing and reduces pain in recurrent aphthous ulcers. The demulcent, anti-inflammatory, and wound-healing properties provide a rational basis. Limited high-quality clinical trial data.
[4]endocrine-metabolic
Type 2 diabetes mellitus (adjunctive glycemic management)
Multiple meta-analyses support a modest blood glucose-lowering effect. Dick et al. (2016) meta-analysis of 9 studies: significant reduction in fasting blood glucose (-46.6 mg/dL) and HbA1c (-1.05%). Suksomboon et al. (2016) meta-analysis of 8 RCTs (n=470): significant improvement in HbA1c in type 2 diabetes (mean difference -11 mmol/mol). Zhang et al. (2016) meta-analysis of 5 RCTs on prediabetes/early diabetes also showed benefit. The gel (not the latex) is the relevant preparation. Mechanisms may include enhanced insulin sensitivity, alpha-glucosidase inhibition, chromium-mediated insulin signaling, and acemannan effects on hepatic glucose metabolism. Effects are modest and supportive — not a replacement for standard diabetes care. Patients on hypoglycemic medications should be monitored for additive effects.
[5, 16, 17, 18]Hyperlipidemia (elevated cholesterol and triglycerides)
Some clinical studies report modest improvements in lipid profiles (total cholesterol, LDL-cholesterol, triglycerides) with oral aloe vera gel supplementation. The phytosterol content (beta-sitosterol, campesterol) may contribute through cholesterol absorption inhibition. Evidence is insufficient for a firm recommendation; larger, well-designed clinical trials are needed.
[5, 10]Immune System
Immunomodulation and immune support (general)
Acemannan and aloeride polysaccharides activate innate immune cells in vitro and in animal models. Acemannan has been licensed as a veterinary immunostimulant for treatment of fibrosarcoma in cats and dogs. In humans, oral acemannan supplementation has been investigated in HIV/AIDS (Pulse et al. 1990, pilot study showing improved symptoms and CD4 counts) but results were not confirmed in larger trials. The immunomodulatory potential of aloe vera polysaccharides is well-established preclinically but human clinical evidence for systemic immune enhancement remains preliminary.
[1, 5]Energetics
Temperature
cool
Moisture
moist
Taste
Tissue States
hot/excitation, dry/atrophy, damp/stagnation (latex only)
Aloe vera has distinctly different energetic profiles depending on the part used. The INNER GEL is cool and moist — a classic cooling demulcent indicated for hot, dry, inflamed tissue states. It soothes heat-related conditions (burns, inflammation, hot digestive irritation) and moistens dry, atrophic tissues. In Ayurveda, Kumari (aloe gel) is classified as tikta (bitter), kashaya (astringent), and madhura (sweet) in rasa (taste), with cooling virya (potency) and madhura vipaka (post-digestive effect). It balances all three doshas, particularly pitta (the fire humor). In TCM, Lu Hui (aloe latex) is classified as bitter and cold, entering the Liver, Stomach, and Large Intestine meridians — clearing liver fire, purging intestinal heat-accumulation, and killing parasites. The LATEX is cold and bitter — a classic purgative indicated for heat/excess constipation (hard, dry, infrequent stools with heat signs). The extreme bitterness addresses damp/stagnation patterns in the liver and gut. The gel and latex thus address complementary but distinct tissue states: the gel for hot/dry conditions requiring cooling moisture, the latex for heat/excess/stagnation conditions requiring purgation. CAVEAT: Herbal energetics are interpretive frameworks within Western herbalism, Ayurveda, and TCM, not standardized across all practitioners.
Traditional Uses
Ancient Egyptian medicine (Ebers Papyrus, ca. 1550 BCE)
- Treatment of skin infections, burns, and wounds
- Cosmetic preparations for skin beauty and embalming
- Internal purgative for intestinal parasites and digestive complaints
- Reportedly used by Cleopatra and Nefertiti as part of beauty regimens
"The Ebers Papyrus (ca. 1550 BCE), one of the oldest preserved medical texts, contains references to aloe as a treatment for skin diseases, burns, and ulcers. Aloe was among the plants used in Egyptian embalming practices. The plant was known as the 'plant of immortality' and was reportedly presented as a funeral gift to pharaohs. Dioscorides (ca. 70 CE) later documented that the finest aloe drug came from Egypt and from the island of Socotra."
Greco-Roman medicine (Dioscorides, Pliny, Galen)
- Purgative and cathartic for intestinal cleansing
- Topical treatment for wounds, hemorrhoids, and skin ulcers
- Hair loss prevention
- Treatment of eye diseases and oral conditions
- Reportedly used by Alexander the Great's army for wound treatment on campaign
"Dioscorides (De Materia Medica, ca. 70 CE) described aloe extensively, distinguishing between Indian and other varieties. He recommended it for wound healing, hemorrhoid treatment, as a purgative, and for various skin conditions. Pliny the Elder (Naturalis Historia) and Galen further documented its uses. The legend holds that Aristotle persuaded Alexander the Great to conquer the island of Socotra to secure its aloe supply for his army's wound care."
Ayurveda (Classical Indian medicine)
- Known as Kumari (meaning 'young girl' or 'virgin') and Ghritkumari
- Classified as a rasayana (rejuvenative) herb, particularly for the female reproductive system
- Treatment of skin diseases, wounds, burns, and inflammatory skin conditions
- Purgative for constipation and liver congestion (virechana)
- Digestive tonic and cholagogue for sluggish digestion and liver stagnation
- Treatment of menstrual irregularities and uterine tonic
- Applied topically to hair and scalp for hair growth and dandruff
- Balances all three doshas, particularly pacifies pitta (fire) and kapha (water/earth)
"In Ayurveda, Kumari (Aloe vera) is one of the most versatile medicinal plants. The Sushruta Samhita and Charaka Samhita both document its uses. Kumari is classified with tikta (bitter), kashaya (astringent), and madhura (sweet) rasa (tastes), sheeta (cooling) virya (potency), and madhura vipaka (post-digestive effect). It acts primarily on the rasa, rakta, mamsa, and shukra dhatus (tissue layers). The fresh gel (kumari swarasa) is used internally as a digestive and rejuvenative, while the dried latex (kumari sara) serves as a purgative. It is considered especially beneficial for women's health and is a key ingredient in the formulation Kumaryasava (a fermented preparation)."
Traditional Chinese medicine (TCM)
- Known as Lu Hui (芦荟), meaning 'black deposit' referring to the dried concentrated latex
- Classified as bitter and cold, entering the Liver, Stomach, and Large Intestine meridians
- Purging intestinal heat-accumulation: cathartic for heat-type constipation with hard, dry stools
- Clearing liver fire: treating liver heat patterns with irritability, headache, red eyes, and dizziness
- Killing intestinal parasites (traditional use for roundworm, pinworm)
- Topically for skin sores, tinea, and eczema
- Cooling blood-heat conditions with skin eruptions
"Lu Hui (aloe latex/dried juice) is documented in classical Chinese materia medica texts including the Bencao Gangmu (Compendium of Materia Medica, Li Shizhen, 1578) and the Kaibao Bencao (ca. 973 CE). It is classified among the 'purgative' (xia yao) category of herbs. TCM primarily uses the concentrated dried latex rather than the fresh gel, emphasizing its bitter, cold, and purgative qualities. Its primary TCM functions are xie xia tong bian (purging and promoting bowel movement), qing gan xie huo (clearing liver fire), and sha chong (killing parasites). The fresh gel is used topically but is not a major oral preparation in classical TCM."
[1]
Unani (Greco-Arabic/Islamic) medicine
- Known as Sibr (صبر) or Elwa
- Purgative for intestinal cleansing and treatment of constipation
- Hepatoprotective and cholagogue for liver disorders
- Treatment of jaundice and splenomegaly
- Topical application for wounds, burns, and skin diseases
- Emmenagogue for promoting menstrual flow
"In the Unani tradition, derived from Greco-Roman medicine and refined by Arabic physicians including Ibn Sina (Avicenna), Sibr (aloe) is classified as hot and dry in the second degree. Avicenna's Canon of Medicine (Al-Qanun fi al-Tibb, ca. 1025 CE) describes aloe as a purgative, hepatoprotective, and wound-healing agent. It was a major trade commodity along the incense routes from Socotra and southern Arabia to the Mediterranean and was one of the most important drugs in the Arab pharmacopoeia."
[1]
Western herbal medicine (European and American eclectic traditions)
- Stimulant laxative for chronic constipation
- Bitter digestive tonic and cholagogue
- Topical vulnerary for burns, wounds, sunburn, and skin irritation
- Demulcent for gastrointestinal inflammation (gel internally)
- Emmenagogue (historical use, now considered contraindicated in pregnancy)
- Component of 'Swedish Bitters' and other traditional bitter formulas
"In the Western herbal tradition, aloe has been used since at least the time of the Anglo-Saxon herbals (Leechbook of Bald, ca. 900 CE). The Eclectics (Felter, Lloyd, King's American Dispensatory) used aloe primarily as a laxative and bitter tonic, particularly for constipation associated with hepatic congestion. Modern Western herbalists (Hoffmann, Mills & Bone) emphasize the distinction between gel and latex: the gel as a topical vulnerary and internal demulcent, the latex as a short-term laxative. Aloe is a common ingredient in traditional European bitter preparations, including 'Swedish Bitters' popularized by Maria Treben."
Modern Research
Aloe vera for burn wound healing (systematic review and meta-analysis)
Systematic review of controlled clinical trials evaluating topical aloe vera for burn wound healing. Four studies (n=371) met inclusion criteria, including RCTs and controlled clinical trials of patients with first- and second-degree burns.
Findings: The pooled weighted mean difference for healing time was significantly shorter for aloe vera compared with control groups: 8.79 days (95% CI: 2.51-15.07, P=0.006) in the subset of one blinded RCT and one non-RCT involving 138 participants with first- and second-degree burns. The review concluded that cumulative evidence supports that aloe vera might be an effective topical treatment for first- and second-degree burns.
Limitations: Only 4 studies met inclusion criteria. Heterogeneous study designs, aloe preparations, and burn severity. Some studies had methodological limitations. The evidence, while positive, was graded as limited in quantity.
[7]
Aloe vera for second-degree burns (recent meta-analysis)
Systematic review and meta-analysis of 9 RCTs evaluating effects of topical aloe vera on burn injuries, with a focus on second-degree burns.
Findings: Aloe vera significantly reduced mean wound-healing time compared to other topical agents (mean difference -3.76 days, P<0.05). Six of the 9 included RCTs provided data on the primary outcome of wound healing time. No significant differences were found in pain reduction or wound infection risk between aloe vera and control groups. The authors concluded that aloe vera expedites wound healing in patients with second-degree burns without increasing infection risk.
Limitations: Moderate heterogeneity across studies. Variable aloe vera preparations, concentrations, and application protocols. Some studies had small sample sizes. Risk of bias was moderate in several included studies.
[8]
Aloe vera clinical effectiveness (comprehensive systematic review)
Comprehensive systematic review to define the clinical effectiveness of aloe vera across all indications. Four independent literature searches of MEDLINE, EMBASE, Biosis, and the Cochrane Library were conducted. Only controlled clinical trials were included.
Findings: Ten studies met inclusion criteria across indications including wound healing, burns, psoriasis, genital herpes, and diabetes. Topical aloe vera was supported for wound healing and genital herpes. Oral aloe vera showed promise for diabetes. Results for psoriasis were contradictory between studies. The review concluded that aloe vera's external use for wound healing was the most convincingly supported indication.
Limitations: Small number of included trials. Variable quality of primary studies. Diverse indications prevented pooled analysis. Published in 1999, does not capture subsequent clinical trial evidence.
[10]
Topical aloe vera for psoriasis vulgaris (placebo-controlled RCT)
Double-blind, placebo-controlled trial of topical 0.5% aloe vera extract in a hydrophilic cream for mild-to-moderate chronic plaque-type psoriasis. Sixty patients were randomized to aloe vera cream or placebo, applied topically 3 times daily for 5 consecutive days per week for up to 4 weeks.
Findings: Aloe vera cream cured 25/30 patients (83.3%) compared to 2/30 (6.6%) with placebo (P<0.001). Psoriatic plaques cleared significantly (82.8% vs. 7.7%, P<0.001). PASI scores decreased from a mean of 9.3 to 2.2 in the aloe group. No adverse drug-related symptoms were reported. The treatment was well tolerated.
Limitations: Single-center study in Pakistan. Relatively small sample (n=60). The remarkably high cure rate (83.3%) has not been replicated in subsequent studies — Paulsen et al. (2005) using a commercial aloe gel found no benefit, suggesting the specific formulation and concentration may be critical. The discrepancy between studies requires resolution through larger, multi-center trials.
[11]
Aloe vera for glycemic control in prediabetes and type 2 diabetes (meta-analysis)
Systematic review and meta-analysis of 8 randomized controlled trials (n=470, 235 prediabetes and 235 type 2 diabetes) evaluating the effect of aloe vera supplementation on glycemic control.
Findings: In type 2 diabetes: aloe vera significantly improved HbA1c (mean difference -11 mmol/mol, P<0.05). In prediabetes: significant improvement in fasting plasma glucose (mean difference -0.22 mmol/L, P<0.05). The review concluded that aloe vera may be a useful adjunct for glycemic control in prediabetes and type 2 diabetes.
Limitations: Moderate-to-high heterogeneity across studies. Variable aloe preparations (gel, juice, extract, different doses). Short study durations (4-12 weeks). Small sample sizes in individual trials. Risk of bias was unclear in several studies. Effects were modest and should not replace standard diabetes treatment.
[16]
Oral aloe vera for reduction of fasting blood glucose and HbA1c (meta-analysis)
Meta-analysis of studies evaluating the effects of oral aloe vera preparations on fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) in humans.
Findings: Nine studies met criteria for FBG analysis (n=283); 5 included HbA1c data (n=89). Oral aloe vera significantly reduced FBG (mean reduction 46.6 mg/dL) and HbA1c (mean reduction 1.05%). The pooled analysis supports a clinically meaningful glycemic benefit of oral aloe vera supplementation.
Limitations: Small total sample sizes. Significant heterogeneity. Variable preparations and dosing. Short study durations. Many studies conducted in regions where aloe is traditionally used, limiting generalizability. Publication bias cannot be excluded.
[17]
Aloe vera gel for mild-to-moderate ulcerative colitis (RCT)
Double-blind, randomized, placebo-controlled trial of oral aloe vera gel (100 mL twice daily for 4 weeks) in 44 patients with mild-to-moderately active ulcerative colitis.
Findings: Clinical remission occurred in 9/30 (30%) aloe vera patients vs. 1/14 (7%) placebo (not statistically significant, but numerically meaningful). Simple Clinical Colitis Activity Index (SCCAI) decreased significantly more in the aloe group (P=0.01). Sigmoidoscopic and histological scores also improved more with aloe vera. The study concluded that oral aloe vera gel appeared to be safe and produced a clinical response more often than placebo in active ulcerative colitis.
Limitations: Small sample size (n=44). Short duration (4 weeks). Single-center. The primary endpoint of clinical remission did not reach statistical significance. Requires replication in larger, multi-center trials. Dose and preparation may need optimization.
[14]
Aloe vera for GERD compared to omeprazole and ranitidine (RCT)
Randomized trial comparing standardized aloe vera syrup (10 mL/day) with omeprazole (20 mg/day) and ranitidine (150 mg twice daily) in patients with GERD over 4 weeks.
Findings: Aloe vera syrup reduced all assessed GERD symptoms (heartburn, food regurgitation, flatulence, belching, dysphagia, nausea, vomiting) at weeks 2 and 4 to a degree comparable to omeprazole and ranitidine. Aloe vera was well tolerated with no significant adverse effects. The authors concluded that aloe vera may provide a safe and effective treatment for reducing GERD symptoms.
Limitations: Single study; not yet replicated. Relatively small sample size. Non-blinded comparison. Short duration (4 weeks). The comparable efficacy to omeprazole for GERD is a strong claim requiring confirmation in larger, blinded trials.
[15]
Aloe vera for oral mucositis (systematic review and meta-analysis of RCTs)
Systematic review and meta-analysis evaluating the effectiveness of aloe vera in the treatment and prevention of oral mucositis in patients undergoing cancer treatment (radiotherapy and/or chemotherapy).
Findings: The meta-analysis confirmed that aloe vera significantly reduces oral mucositis severity and duration compared to control/placebo groups. Aloe vera mouthwash and topical gel applications were the most studied formulations. The combined evidence supports aloe vera as a beneficial complementary intervention for managing cancer treatment-induced oral mucositis.
Limitations: Heterogeneity in aloe vera preparations, concentrations, and application methods across studies. Variable cancer types and treatment protocols. Some included studies had small sample sizes. Quality of evidence was moderate overall.
[20]
Topical aloe vera for genital herpes (placebo-controlled RCT)
Double-blind, placebo-controlled RCT evaluating 0.5% aloe vera extract cream for first episodes of genital herpes in 120 men.
Findings: Aloe vera extract cream significantly shortened mean healing time compared to both aloe vera gel alone and placebo cream. Healing time in the aloe cream group was 4.8 days vs. 7.9 days (aloe gel) and 14.0 days (placebo), P<0.001. The cure rate was significantly higher in the aloe extract cream group (67%) compared to placebo (6.7%). No adverse effects were reported.
Limitations: Male participants only. First episode herpes only (no data on recurrent herpes). Single-center study in Pakistan. The preparation was a specific 0.5% extract in a hydrophilic cream, which may not be equivalent to commercial aloe products. Requires replication, particularly with inclusion of female participants and recurrent episodes.
[13]
Preparations & Dosage
topical-gel
Strength: Fresh inner leaf gel (100%) or commercial gel with minimum 90% aloe vera gel content. For psoriasis (per Syed 1996): 0.5% aloe vera extract in hydrophilic cream.
For topical use: apply fresh inner leaf gel directly from a freshly cut leaf, or use a commercial stabilized aloe vera gel (minimum 90-98% aloe vera gel content, verified by IASC certification). For fresh gel: cut a mature outer leaf from the base of the plant, slice off the flat sides or split the leaf lengthwise, and scoop out the clear, colorless inner gel. Apply directly to the affected skin area in a thin, even layer. Allow to dry naturally. Reapply 2-3 times daily. For burns: apply after initial cooling of the burn under cold running water for 10-20 minutes. Commercial gels should list aloe vera gel (or Aloe barbadensis leaf juice) as the first or second ingredient and should be free of added alcohol, artificial fragrances, and coloring agents that may irritate damaged skin.
Apply liberally to affected area 2-4 times daily as needed. No strict dose limitation for topical gel application.
2-4 times daily or as needed for symptomatic relief
For acute wounds/burns: continue until healing is complete. For chronic conditions (psoriasis, eczema): may be used long-term as tolerated.
Safe for topical use in children of all ages. Apply as for adults. Avoid oral ingestion in children under 12.
Fresh gel from a living plant is traditionally considered optimal for topical wound care, as processing may reduce enzyme activity and polysaccharide integrity. Commercial products vary enormously in quality — many contain very little actual aloe vera gel despite prominent labeling. Look for IASC (International Aloe Science Council) certification, which verifies minimum aloe content and purity. Products should contain less than 10 ppm aloin (indicating proper gel-latex separation). Avoid products with alcohol, parabens, or artificial fragrances for wound care applications.
oral-gel-juice
Strength: Inner leaf gel juice: typically 1:1 (pure gel juice) or concentrated. Gel powder: standardized to acemannan/polysaccharide content (commonly 10-30% acemannan by weight).
For internal use: commercially prepared, stabilized aloe vera inner gel juice or concentrate, properly filtered and processed to remove latex/anthraquinone contamination (aloin content <10 ppm per IASC standards). Available as liquid juice (typically diluted to 1:1 or consumed as-is) or as concentrated gel powder in capsules. For GERD: 10 mL standardized aloe vera syrup per day. For ulcerative colitis (per Langmead 2004): 100 mL aloe vera gel twice daily. For glycemic support: dosages vary across studies from 100-300 mg/day of concentrated gel extract to 30-300 mL/day of gel juice.
Liquid gel juice: 30-100 mL twice daily. Gel powder (capsules): 100-300 mg daily standardized to acemannan content. For specific conditions, follow study-based protocols.
1-2 times daily
May be used for 4-12 weeks for specific therapeutic courses. Long-term use of properly processed inner gel is generally considered safe.
Not recommended for children under 12 for internal use due to lack of pediatric safety data.
CRITICAL: Oral aloe vera gel products must be clearly distinguished from aloe latex/whole leaf products. Only properly processed inner gel products (with verified low aloin content, <10 ppm) should be used for long-term oral supplementation. 'Whole leaf' aloe juices, even if decolorized, may contain residual anthraquinones and should be used with caution. The 2013 NTP rodent bioassay raised safety concerns specifically about non-decolorized whole leaf extract, not about purified inner gel. Look for IASC certification for quality assurance.
capsule-tablet (latex/laxative preparation)
Strength: Standardized to 20-30 mg hydroxyanthracene derivatives (as aloin) per daily dose. Products should specify anthraquinone glycoside content on labeling.
For constipation: standardized aloe latex (dried juice) preparations in capsule or tablet form, standardized to hydroxyanthracene derivative content (calculated as aloin). Take the minimum effective dose at bedtime; bowel movement typically occurs in 6-12 hours. Per Commission E: the dose should provide 20-30 mg hydroxyanthracene derivatives per day, calculated as aloin. Individual dosing should start at the lower end and increase only if needed.
20-30 mg hydroxyanthracene derivatives (calculated as aloin) daily at bedtime. Start with the lowest dose that produces a comfortable soft stool. Equivalent to approximately 50-200 mg of dried aloe latex extract depending on standardization.
Once daily at bedtime
MAXIMUM 1-2 weeks continuous use. Not for chronic constipation management. If constipation persists beyond 1 week, investigate underlying cause.
Contraindicated in children under 12 years (Commission E, EMA).
This preparation uses aloe LATEX (dried juice), NOT the gel. It is a potent stimulant laxative with a strict safety profile. The Commission E, WHO, and EMA all specify short-term use only (1-2 weeks maximum) and a dose providing 20-30 mg hydroxyanthracene derivatives. Chronic use can cause electrolyte depletion (especially potassium), melanosis coli (harmless but diagnostic pigmentation of the colonic mucosa), and theoretical risk of colonic nerve damage with laxative dependency. Contraindicated in pregnancy, nursing, intestinal obstruction, Crohn's disease, ulcerative colitis, appendicitis, and in children under 12. Must not be confused with aloe vera gel supplements.
mouthwash
Strength: 70-100% aloe vera inner gel juice, or commercial aloe vera mouthwash (check for aloe content and absence of alcohol, which would aggravate mucositis).
Aloe vera mouthwash for oral mucositis and oral lichen planus: prepare by diluting stabilized aloe vera inner gel juice to a suitable concentration (typically 70-100% aloe gel content) or use commercial aloe vera mouthwash products. Swish 15-30 mL in the mouth for 30-60 seconds, then spit out. Can be swallowed if desired (inner gel is safe for oral consumption). For radiation-induced mucositis: begin use at the start of radiotherapy and continue throughout treatment.
15-30 mL per use, 3-4 times daily or as needed for symptom relief.
3-4 times daily, especially after meals and at bedtime
For mucositis: throughout cancer treatment course and until lesions resolve. For oral lichen planus: as needed for symptom management.
May be used in children under supervision if they can reliably spit. Reduce volume to 5-10 mL.
Alcohol-free formulations are essential for oral mucositis patients, as alcohol causes burning and further mucosal damage. The aloe vera gel's demulcent, anti-inflammatory, and wound-healing properties make it particularly suitable for oral mucosal conditions. In the Mansouri et al. (2016) trial, aloe vera mouthwash was found comparable to benzydamine (a standard-of-care anti-inflammatory mouthwash) for radiation-induced oral mucositis.
poultice-compress
Strength: Fresh inner leaf gel directly from the plant, or commercial aloe vera gel (minimum 90% content).
For direct wound application: split a freshly cut aloe leaf lengthwise and apply the gel side directly to the wound or burn, securing with gauze bandage. Alternatively, spread a thick layer of fresh or commercial aloe gel on sterile gauze and apply as a compress. Change every 4-8 hours or when the gel dries out.
Apply fresh gel or gel-soaked compress directly to the wound. Cover entire affected area.
Change compress every 4-8 hours or as needed
Continue until wound healing is complete
Same application as adults.
This is the most traditional method of applying aloe vera — directly from the living plant. Many households in tropical and subtropical regions keep aloe plants specifically for first-aid burn and wound treatment. The fresh gel provides maximum enzyme activity (bradykinase, SOD, catalase) that diminishes with commercial processing. For significant burns, apply after initial cooling under cold water and seek medical attention for burns larger than the patient's palm.
Safety & Interactions
Class 2b
Not to be used during lactation (AHPA Botanical Safety Handbook)
Contraindications
Aloe LATEX (stimulant laxative) is absolutely contraindicated in intestinal obstruction, stenosis, or atony because stimulating peristalsis against a mechanical obstruction risks perforation, and stimulant laxatives are ineffective and dangerous in atonic bowel conditions. This contraindication applies to all anthraquinone-containing laxative preparations.
Aloe LATEX is contraindicated in acute inflammatory bowel disease because the stimulant cathartic action and irritant effects of anthraquinones can aggravate intestinal inflammation, worsen diarrhea, and exacerbate electrolyte losses in already compromised patients. NOTE: This contraindication applies specifically to the anthraquinone-containing latex. The gel (free of anthraquinones) has been studied FOR ulcerative colitis treatment (Langmead et al. 2004) and may actually be beneficial — a critical distinction.
Stimulant laxatives are contraindicated when appendicitis is suspected or when abdominal pain of unknown cause is present, as stimulating peristalsis may precipitate perforation of an inflamed appendix or worsen an acute abdominal emergency.
Commission E, WHO, and EMA all contraindicate oral aloe latex preparations in children under 12 years due to the risk of severe electrolyte disturbance and dehydration from the stimulant laxative effect. Topical gel application is safe in children of all ages.
Although rare, contact dermatitis and allergic reactions to aloe vera have been reported, particularly in individuals with existing allergies to plants in the Liliaceae or Asphodelaceae families (garlic, onions, tulips). A patch test is recommended before extensive topical use in sensitized individuals.
Drug Interactions
| Drug / Class | Severity | Mechanism |
|---|---|---|
| Cardiac glycosides (digoxin, digitoxin) (Cardiac glycosides) | moderate | LATEX ONLY. Chronic use of aloe latex causes potassium depletion (hypokalemia) through intestinal losses. Hypokalemia potentiates the toxicity of cardiac glycosides by enhancing binding to the sodium-potassium ATPase, increasing the risk of fatal cardiac arrhythmias (ventricular tachycardia, fibrillation) even at therapeutic digoxin levels. |
| Thiazide diuretics, loop diuretics (hydrochlorothiazide, furosemide, etc.) (Diuretics) | moderate | LATEX ONLY. Additive potassium depletion. Both anthraquinone laxatives and potassium-wasting diuretics cause renal and intestinal potassium losses. Combined use significantly increases the risk of clinically significant hypokalemia. |
| Systemic corticosteroids (prednisone, dexamethasone, etc.) (Corticosteroids) | moderate | LATEX ONLY. Systemic corticosteroids cause potassium wasting (mineralocorticoid effect). Combined with the potassium-depleting effect of chronic anthraquinone laxative use, the risk of hypokalemia is increased. |
| Insulin, metformin, sulfonylureas, and other antidiabetic medications (Hypoglycemic agents) | minor | GEL (oral). Aloe vera gel taken orally has been shown to modestly reduce fasting blood glucose and HbA1c in clinical studies. Additive hypoglycemia is theoretically possible when combined with pharmaceutical antidiabetic agents, particularly insulin and sulfonylureas. |
| Anticoagulants (warfarin) and antiplatelet agents (Anticoagulants/Antiplatelets) | theoretical | LATEX ONLY (via hypokalemia). Severe hypokalemia from chronic anthraquinone laxative abuse can alter cardiac conduction and theoretically complicate anticoagulant management. Additionally, sevoflurane anesthesia in a patient taking long-term aloe vera was associated with excess intraoperative bleeding in one case report, though the mechanism is unclear. |
| Other stimulant laxatives (senna, cascara, bisacodyl) (Stimulant laxatives) | moderate | LATEX ONLY. Additive cathartic effects and increased risk of electrolyte depletion, dehydration, and colonic irritation when multiple stimulant laxatives are combined. |
Pregnancy & Lactation
Pregnancy
unsafe
Lactation
unsafe
LATEX: Contraindicated in pregnancy (AHPA Class 2b). Anthraquinone glycosides and their metabolites may stimulate uterine contractions, and the griping and electrolyte disturbance caused by stimulant laxatives can precipitate premature labor. Aloe-emodin has been detected in breast milk in animal studies — aloe latex is contraindicated during lactation (AHPA Class 2c). The Commission E, WHO, and EMA all contraindicate aloe latex in pregnancy and nursing. GEL: Topical use of aloe vera gel during pregnancy and lactation is generally considered safe — there are no known risks from external application. Oral use of inner gel products during pregnancy has limited safety data. Some animal studies suggest high oral doses may have uterotoxic effects, though the gel is far less potent than the latex in this regard. As a precautionary measure, therapeutic oral doses of aloe vera gel are best avoided during pregnancy unless the benefit clearly outweighs the theoretical risk. Topical gel application on the breasts should be cleaned before nursing to avoid infant ingestion.
Adverse Effects
References
Monograph Sources
- [1] World Health Organization. WHO Monographs on Selected Medicinal Plants, Volume 1: Aloe (Aloe Vera Gel) and Aloe (Aloe). World Health Organization, Geneva (1999)
- [2] German Commission E (Bundesinstitut für Arzneimittel und Medizinprodukte). Commission E Monograph: Aloe (Aloe barbadensis; Aloe capensis). Bundesanzeiger (Federal Gazette), Germany. English translation in: Blumenthal M, et al. (eds). The Complete German Commission E Monographs. American Botanical Council, Austin, TX (1998)
- [3] European Medicines Agency, Committee on Herbal Medicinal Products (HMPC). European Union Herbal Monograph on Aloe barbadensis Mill. and on Aloe (various species, mainly Aloe ferox Mill. and its hybrids), folii succus siccatus. European Medicines Agency, London (2016)
- [4] Hoffmann D. Medical Herbalism: The Science and Practice of Herbal Medicine. Healing Arts Press, Rochester, VT (2003)
- [5] Mills S, Bone K. Principles and Practice of Phytotherapy: Modern Herbal Medicine (2nd edition). Churchill Livingstone/Elsevier, Edinburgh (2013)
- [6] Gardner Z, McGuffin M (eds). American Herbal Products Association's Botanical Safety Handbook (2nd edition). CRC Press/Taylor & Francis, Boca Raton, FL (2013)
Clinical Studies
- [7] Maenthaisong R, Chaiyakunapruk N, Niruntraporn S, Kongkaew C. The efficacy of aloe vera used for burn wound healing: a systematic review. Burns (2007) ; 33 : 713-718 . DOI: 10.1016/j.burns.2006.10.384 . PMID: 17499928
- [8] Zheng X, et al.. Effects of Aloe vera on Burn Injuries: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Burn Care Res (2024) ; 45 : 1536-1544 . DOI: 10.1093/jbcr/irae053 . PMID: 38605441
- [9] Sharma S, et al.. Second-Degree Burns and Aloe Vera: A Meta-analysis and Systematic Review. J Burn Care Res (2022) . PMID: 36264753
- [10] Vogler BK, Ernst E. Aloe vera: a systematic review of its clinical effectiveness. Br J Gen Pract (1999) ; 49 : 823-828 . PMID: 10885091
- [11] Syed TA, Ahmad SA, Holt AH, Ahmad SA, Ahmad SH, Afzal M. Management of psoriasis with Aloe vera extract in a hydrophilic cream: a placebo-controlled, double-blind study. Trop Med Int Health (1996) ; 1 : 505-509 . PMID: 8765459
- [12] Paulsen E, Korsholm L, Brandrup F. A double-blind, placebo-controlled study of a commercial Aloe vera gel in the treatment of slight to moderate psoriasis vulgaris. J Eur Acad Dermatol Venereol (2005) ; 19 : 326-331 . PMID: 15857459
- [13] Syed TA, Afzal M, Ahmad SA, Holt AH, Ahmad SA, Ahmad SH. Management of genital herpes in men with 0.5% Aloe vera extract in a hydrophilic cream: a placebo-controlled double-blind study. J Dermatol Treat (1997) ; 8 : 99-102
- [14] Langmead L, Feakins RM, Goldthorpe S, Holt H, Tsironi E, De Silva A, Jewell DP, Rampton DS. Randomized, double-blind, placebo-controlled trial of oral aloe vera gel for active ulcerative colitis. Aliment Pharmacol Ther (2004) ; 19 : 739-747 . DOI: 10.1111/j.1365-2036.2004.01902.x . PMID: 15043514
- [15] Panahi Y, Khedmat H, Valizadegan G, Mohtashami R, Sahebkar A. Efficacy and safety of Aloe vera syrup for the treatment of gastroesophageal reflux disease: a pilot randomized positive-controlled trial. J Tradit Chin Med (2015) ; 35 : 632-636 . PMID: 26742306
- [16] Suksomboon N, Poolsup N, Punthanitisarn S. Effect of Aloe vera on glycaemic control in prediabetes and type 2 diabetes: a systematic review and meta-analysis. J Clin Pharm Ther (2016) ; 41 : 180-188 . DOI: 10.1111/jcpt.12382 . PMID: 27009750
- [17] Dick WR, Fletcher EA, Shah SA. Reduction of Fasting Blood Glucose and Hemoglobin A1c Using Oral Aloe Vera: A Meta-Analysis. J Altern Complement Med (2016) ; 22 : 450-457 . DOI: 10.1089/acm.2015.0122 . PMID: 27152917
- [18] Zhang Y, Liu W, Liu D, Zhao T, Tian H. Efficacy of Aloe Vera Supplementation on Prediabetes and Early Non-Treated Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients (2016) ; 8 : 388 . DOI: 10.3390/nu8070388 . PMID: 27347994
- [19] Mansouri P, Haghighi M, Beheshtipour N, Ramzi M. Comparative Efficacy of Aloe vera and Benzydamine Mouthwashes on Radiation-induced Oral Mucositis: A Triple-blind, Randomised, Controlled Clinical Trial. Oral Health Prev Dent (2016) ; 14 : 253-258 . PMID: 25431805
- [20] Wang L, et al.. Effectiveness of Aloe vera in the treatment of oral mucositis: a systematic review and meta-analysis of randomized controlled trials. Oral Oncol (2025) . PMID: 39909775
- [21] Choonhakarn C, Busaracome P, Sripanidkulchai B, Sarakarn P. The efficacy of aloe vera gel in the treatment of oral lichen planus: a randomized controlled trial. Br J Dermatol (2008) ; 158 : 573-577 . DOI: 10.1111/j.1365-2133.2007.08370.x . PMID: 18076705
- [22] Hashemi SA, Madani SA, Abediankenari S. The Effect of Aloe Vera Clinical Trials on Prevention and Healing of Skin Wound: A Systematic Review. Iran J Med Sci (2015) ; 40 : 1-9 . PMID: 30666070
Traditional Texts
- [23] Anonymous (Ancient Egyptian). Ebers Papyrus (Papyrus Ebers). Original text ca. 1550 BCE; housed at the University of Leipzig. Multiple modern translations available. (-1550)
- [24] Pedanius Dioscorides. De Materia Medica. Original text ca. 70 CE; multiple modern translations (70)
Pharmacopeias & Reviews
- [25] British Herbal Medicine Association. British Herbal Pharmacopoeia: Aloe barbadensis, Aloe Vera Gel. British Herbal Medicine Association, Bournemouth (1983)
- [26] United States Pharmacopeia. USP Monograph: Aloe. United States Pharmacopeial Convention, Rockville, MD (2023)
Last updated: 2026-03-02 | Status: review
Unlock the Full Materia Medica
This monograph is part of our complete evidence-based herbal reference. Enter your email to get free, unlimited access to all of our monographs.
No spam, ever. Unsubscribe anytime.
You're In!
You now have full access to all of our herbal monographs.