Clinical

Although Aloe vera products are used for many indications, the chief use is treating skin conditions. SKIN CONDITIONS

Aloe is used in the treatment of wounds, burns, radiation burns, ulcers, frostbite, psoriasis and genital herpes. The healing properties may be attributed to antimicrobial, immune-stimulating, anti-inflammatory and antithromboxane activities. Allantoin has also been shown to stimulate epithelialisation, and acemannan has been shown to stimulate macrophage production of IL-1 and TNF, which are associated with wound healing (Liptak 1997).

Most human studies have found that topical application of aloe vera gel increases wound healing rate and effectively reduces microbial counts; however, there are some negative studies, most likely related to the fact that the composition of aloe vera gel varies, even within the same species. Chemical composition depends on source, climate, region, and the processing method used (Choi & Chung 2003).

Dry-coated aloe vera gloves were tested by 30 women suffering from dry, cracked hands, with or without contact dermatitis due to occupational exposure, in an open contralateral comparison study (West & Zhu 2003). Women wore a glove on one hand for 8 hours daily for 30 days followed by a rest period for 30 days and then 10 more days of treatment. Results indicated that the aloe vera glove significantly Aloe vera 23

reduced dry skin, irritation, wrinkling, dermatitis, redness and improved skin integrity.

It would be Interesting to see this study repeated using a standard non-aloe fortified glove on the opposing hand.

The effects of aloe gel applied to skin following dermabrasion in humans are more controversial, with some patients responding well (Fulton 1990), while others have had severe adverse reactions, including burning sensations and dermatitis (Hunter & Frumkin 1991). A standard polyethylene oxide gel dressing saturated with stabilised aloe vera gel was compared to the standard oxide dressing alone in the study by Fulton. The addition of Aloe vera produced a significant vasoconstriction and antiinflammatory effect 24 and 48 hours after application. By the 4th day it produced less crusting and exudate and by the 5th and 6th day re-epithelialisation was almost complete (90% for aloe compared with 50% for the standard treatment). Overall, wound healing was quicker with A. vera and completed by an average of 72 hours before the oxide gel-treatment.

In contrast, one study found that topical aloe vera gel actually slowed healing after caesarean delivery (Schmidt & Greenspoon 1991).

Burns One study involving 27 patients with a partial-thickness burn injury found that topical aloe gel significantly increased the healing rate compared with controls who used a vaseline gauze. The mean healing time for the aloe gel group was 11.89 days compared with the control group, which was 18.18 days. Additionally, the aloe treatment brought about full epithelialisation after 14 days (Visuthikosol et al 1995).

Another study involving 18 outpatients with moderate to deep second-degree burns ranging from 2% to 12% of total body surface area showed that a commercial aloe vera ointment was as effective as SSD in regard to protection against bacterial colonisation and healing time. More specifically, the mean healing time with aloe vera treatment was 13 days compared with 16.15 days for SSD (Hecket al 1981).

Results are less encouraging for sunburn protection and healing. A randomised double-blind trial in 20 healthy volunteers evaluated the effect of aloe vera cream for both prevention and treatment of sunburn (Puvabanditsin & Vongtongsri 2005). The cream (70% aloe) was applied 30 minutes before, immediately after, or both before and after UV irradiation. The cream was then continually applied daily for 3 weeks. The results showed that the aloe vera cream did not protect against sunburn and was not an effective treatment.

Frostbite In combination with other treatments, topical Aloe vera significantly enhances healing and has a beneficial effect in frostbite. One clinical study compared the effects of topical aloe vera cream in combination with standard treatment, such Aloe vera 24

as rapidly rewarming the affected areas, analgesics, antibiotics and debridement

(n = 56) with another group of 98 patients who did not receive aloe vera treatment. Of those receiving aloe vera in addition to usual treatment, 67% healed without tissue loss compared with 32.7% in the control group. Additionally, 7.1 % of the total group of 56 required amputation compared with 32.7% in the control group. Although encouraging, this study is difficult to interpret because the groups were not well matched and combination therapies differed (Heggers et al 1987). Radiation-induced dermatitis A recent review concluded that aloe gel was as effective as mild steroid creams, such as 1% hydrocortisone, to reduce the severity of radiation burn, without the side-effects associated with steroid creams (Maddocks-Jennings et al 2005). In contrast, another review concluded that aloe was ineffective for the prevention or reduction of side-effects to radiation therapy in cancer patients (Richardson et al 2005). That review analysed 1 past review, 5 published RCTs and 2 unpublished RCTs. It is important to note that various preparations such as creams, juices, gels and fresh aloe had been tested, which makes it difficult to assess the evidence.

Ulcers A number of case reports tell of a positive effect on leg ulcers with topical use of aloe gel, including cases that did not respond to standard medical interventions (Zawahry et al 1973). Application of water-based aloe-gel saline soaks, broad-spectrum antibiotics and antifungals allowed a wound, caused by necrotising fasciitis, to heal in 45 days in a 72-year-old woman. Aloe gel and saline-soaked sponges were also used to treat two large seroma cavities caused by deep vein thrombosis in a 48-year-old man (Ardire 1997).

Although aloe gel is commonly used as a topical agent for wound healing it is also used internally. A small study of six patients with chronic leg ulcers found that ingesting 60 mL aloe juice daily and applying aloe gel directly to the ulcer and surrounding area resulted in less exudate, odour and seepage through the bandaging (Atherton 1998).

Psoriasis A double-blind placebo-controlled study found topical aloe vera extract 0.5% in a hydrophilic cream to be beneficial in the treatment of psoriasis. Sixty patients aged 18-50 years with slight to moderate chronic psoriasis and PASI (psoriasis area and severity index) scores between 4.8 and 16.7 (mean 9.3) participated in the study, which was scheduled for 16 weeks with 12 months of follow-up. Patients were examined on a weekly basis and those showing a progressive reduction of lesions, desquamation followed by decreased erythema, infiltration and lowered PASI score were considered healed. By the end of the study, the aloe vera extract cream had cured 83.3% of patients compared with the placebo cure rate of 6.6% (P < 0.001). Psoriatic plaques decreased in 82.8% of patients versus only 7.7%

in the placebo group (P < 0.001). PASI scores decreased to a mean of 2.2 (Syed et al 1996a). In contrast, a randomised, double-blind, placebo-controlled trial found no significant benefits with a commercial aloe vera gel in 41 patients with stable plaque psoriasis (Paulsen et al 2005). Following a 2-week washout period patients applied either the aloe gel or placebo twice daily for 1 month. Redness and desquamation decreased by 72.5% in the active treatment group as compared to 82.5% in the placebo group. It should be pointed out that 82.5% is an extremely high placebo responder rate. Fifty-five per cent of patients reported local side-effects, mainly drying of the skin on test areas.

Genital herpes Two clinical studies have investigated the effects of Aloe vera 0.5% topical preparations in genital herpes, producing good results.

A double-blind, placebo-controlled study has demonstrated that aloe vera extract (0.5%) in a hydrophilic cream is more efficacious than placebo in the treatment of initial episodes of genital herpes in men (n = 60, aged 18-40 years). Each patient was provided with a 40 g tube, containing placebo or active preparation with instructions on self-application of the trial medication to their lesions three times daily for 5 consecutive days (maximum 1 5 topical applications per week). The treatment was well tolerated by all patients (Syed et al 1997).

The other study involving 120 subjects used a preparation containing 0.5% of whole aloe leaf extract in hydrophilic castor and mineral oil cream base, which was applied three times daily for 5 days per week for 2 weeks. Treatment resulted in a shorter mean duration of healing compared with placebo. Aloe cream also increased the overall percentage of healed patients and there were no significant adverse reactions reported (Syed et al 1996b).

The acemannan component of Aloe vera has been used as adjunctive therapy to antiretroviral therapy in HIV infection. A preliminary clinical trial found that acemannan may enhance the activity of the anti-HIV drug AZT. A dose of 800 mg acemannan daily significantly increased circulating monocytes (macrophages) in 14 HIV patients. Aloe increased the number and activity of the monocytes (McDaniel et al 1990). Subsequently, a randomised, double-blind placebo-controlled study of 63 male subjects with advanced HIV, taking zidovudine and didanosine, investigated the effects of 400 mg of acemannan taken four times daily for 48 weeks. Results showed a decrease in CD4 cell numbers in the acemannan group compared with placebo (Montaner et al 1996).

Aloe and Your Health

Aloe and Your Health

This іѕ а health guide, whісh саn hеlр people knоw hоw tо mаkе uѕе оf Aloe vera tо improve оvеrаll health аnd deal wіth mаnу kinds оf diseases.

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