Skin Ulcers

Aloe vera has been used historically to improve wound healing and contains several constituents that may be important for this effect. A group of three patients who had chronic skin ulcerations for 5, 7, and 15 years, respectively, had a rapid reduction in ulcer size after the application of aloe gel on gauze bandages to the ulcers, according to a preliminary report.¹ A controlled study found most patients with pressure ulcers had complete healing after applying an aloe hydrogel dressing to the ulcers every day for ten weeks.² However, this result was not significantly better than that achieved with a moist saline gauze dressing. The amorphous hydrogel dressing used in the above study and derived from the aloe plant (Carrasyn Gel Wound Dressing, Carrington Laboratories, Irving, TX) is approved by the U.S. Food and Drug Administration for the management of mild to moderate skin ulcers.

A double-blind trial found that a combination of 900 mg per day of diosmin and 100 mg per day of hesperidin, two members of the flavonoid family, resulted in significantly greater healing of venous leg ulcers after two months.^3,4 Related flavonoids known as hydroxyethylrutosides have also been investigated for venous ulcer healing. While one controlled study reported significant additional benefit when 2,000 mg per day of hydroxyethylrutosides were added to compression stocking therapy,⁵ another double-blind trial using 1,000 mg per day found no effect on ulcer healing;⁶ a second double-blind trial found no effect of 1,000 mg per day hydroxyethylrutosides on the prevention of venous ulcer recurrences.⁷

Pressure ulcers and diabetic ulcers frequently develop in malnourished and/or institutionalized people. A double-blind study⁸ of malnourished people compared topical application of 20 ml of a solution containing essential fatty acids (EFAs) and linoleic acid extracted from sunflower oil with a control solution containing topical mineral oil. Each solution was applied to the skin three times per day. Compared with the control solution, the solution containing EFAs significantly reduced the incidence of pressure ulcers and improved the hydration and elasticity of the skin.

A preliminary report suggested that evening primrose oil improves blood flow to the legs and heals or reduces the size of venous leg ulcers.⁹ No controlled research has further investigated this claim.

An older preliminary report suggested that large amounts of folic acid given both orally and by injection could promote healing of chronic skin ulcers due to poor circulation.¹⁰ No controlled research has further investigated this claim.

Gotu kola (Centella asiatica) extracts are sometimes used topically to help speed wound healing. Test tube studies have found that extracts of gotu kola high in the active triterpene constituents asiaticosides, madecassoides, asiatic acids, and madecassic acids increase collagen synthesis.^11,12 An animal study found that topical application of asiaticoside isolated from gotu kola, used in a 0.2% solution, improved healing in nonulcer skin wounds.¹³ An overview of three small human clinical trials suggests that topical use of an ointment or powder containing a gotu kola extract high in the active triterpene compounds may speed wound healing in people with slow-healing skin ulcers.¹⁴ These studies used either a topical ointment with a 1% extract concentration or a powder with a 2% extract concentration. People in these studies were typically treated with intramuscular injections of either isolated asiaticosides or the mixed triterpenes three times per week while using the topical ointment or powder.

A controlled trial found that topical application of a hyaluronic acid compound with compression bandaging was significantly better than bandaging alone for healing chronic venous skin ulcers.¹⁵No research has investigated whether oral hyaluronic acid supplements might be similarly effective.

Antioxidants such as vitamin C, vitamin E, and glutathione are depleted in healing skin tissue.¹⁸ One animal study found that vitamin E (alpha-tocopherol) applied to the skin shortened the healing time of skin ulcers.¹⁹ Another animal study reported that administration of oral vitamin E before skin lesions were introduced into the skin prevented some of the tissue damage associated with the development of pressure ulcers.²⁰ A controlled human trial found that 400 IU of vitamin E daily improved the results of skin graft surgery for chronic venous ulcers.²¹ No further research has investigated the potential benefit of vitamin E for skin ulcers.

Animal research has suggested that vitamin C may help prevent skin ulcers,²² and in a preliminary study,²³ elderly patients with pressure ulcers had lower blood levels of vitamin C than did ulcer-free patients. Supplementation with vitamin C (3 grams per day) increased the speed of healing of leg ulcers in patients with a blood disorder called thalassemia, according to a double-blind study.²⁴ And while a double-blind trial of surgical patients with pressure ulcers found that supplementation with 500 mg of vitamin C twice a day accelerated ulcer healing,²⁵ a similar double-blind trial found no difference in the effectiveness of either 20 mg per day or 1,000 mg per day of vitamin C.²⁶

Antioxidants such as vitamin C, vitamin E, and glutathione are depleted in healing skin tissue.²⁷ One animal study found that vitamin E (alpha-tocopherol) applied to the skin shortened the healing time of skin ulcers.²⁸ Another animal study reported that administration of oral vitamin E before skin lesions were introduced into the skin prevented some of the tissue damage associated with the development of pressure ulcers.²⁹ A controlled human trial found that 400 IU of vitamin E daily improved the results of skin graft surgery for chronic venous ulcers.³⁰ No further research has investigated the potential benefit of vitamin E for skin ulcers.

Zinc plays an important role in tissue growth processes important for skin ulcer healing. One study reported that patients with pressure ulcers had lower blood levels of zinc and iron than did patients without pressure ulcers,³¹ and preliminary reports suggested zinc supplements could help some types of skin ulcer.³² Supplementation with 150 mg of zinc per day improved healing in a preliminary study of elderly patients suffering from chronic leg ulcers.³³ Double-blind trials using 135 to 150 mg of zinc daily have shown improvement³⁴ only in patients with low blood zinc levels,³⁵ and no improvement in leg ulcer healing.^36,37 A double-blind trial of 150 mg zinc per day in people with skin ulcers due to sickle cell anemia found that the healing rate was almost three times faster in the zinc group than in the placebo group after six months.³⁸ Lastly, a preliminary study of patients with skin ulcers due to leprosy found that 50 mg of zinc per day in addition to anti-leprosy medication resulted in complete healing in most patients within 6 to 12 weeks.³⁹ Long-term zinc supplementation at these levels should be accompanied by supplements of copper and perhaps calcium, iron, and magnesium. Large amounts of zinc (over 50 mg per day) should only be taken under the supervision of a doctor.

Topically applied zinc using zinc-containing bandages has improved healing of leg ulcers in double-blind studies of both zinc-deficient⁴⁰ and elderly individuals.⁴¹ Most controlled comparison studies have reported that these bandages are no more effective than other bandages used in the conventional treatment of skin ulcers,^42,43 but one controlled trial found non-elastic zinc bandages superior to alginate dressings or zinc-containing elastic stockinettes.⁴⁴ Two controlled trials of zinc-containing tape for foot ulcers due to leprosy concluded that zinc tape was similarly effective, but more convenient than conventional dressings.^45,46

Antioxidants such as vitamin C, vitamin E, and glutathione are depleted in healing skin tissue.⁴⁹ One animal study found that vitamin E (alpha-tocopherol) applied to the skin shortened the healing time of skin ulcers.⁵⁰ Another animal study reported that administration of oral vitamin E before skin lesions were introduced into the skin prevented some of the tissue damage associated with the development of pressure ulcers.⁵¹ A controlled human trial found that 400 IU of vitamin E daily improved the results of skin graft surgery for chronic venous ulcers.⁵² No further research has investigated the potential benefit of vitamin E for skin ulcers.