USE OF HONEY IN HEALING VENOUS ULCERS
ALKA BHIDE (medicalstudent)
For thousands of years honey has served as a natural remedy for numerous ailments. Many believe that the therapeutic potential of uncontaminated, pure honey needs to be explored and for it to have a place in conventional medicine.
Venous ulcers in the lower limb are one of the many complications resulting from deep vein thrombosis (DVT). Deep vein thromboses undergo organisation and recanalisation and in the process valves of the deep veins may be damaged. This leads to the valves becoming incompetent and reflux occurs resulting in chronic venous insufficiency (usually takes a period of years to develop) in the post-thrombotic limb. In the normal adult limb, the venous pressure while standing is approx. 125cmH2O and decreases while walking due to the calf pump. In the post-thrombotic limb, incompetent deep venous valves allow reflux causing the ankle pressure to remain high during calf muscle activity. This leads to incompetence of the valves in perforating veins and blood is forced into the superficial system. The result is disruption of the normal vascular dynamics of the skin and subcutaneous tissues and may cause impaired skin vitality and healing. As aforementioned venous ulceration, commonly above the medial malleolus is a characteristic sign in the post-thrombotic limb.
Conventional treatment of ulcers involves support and compression of the skin and superficial tissues. This can be done either by elastic bandages or correctly sized graded stockings. One must be careful of ensuring that the pressure of these stockings does not cause ischaemia or abrasions over tendons or bony prominences. The presence of infection confined to the ulcer requires excision of the dead tissue and dressing the site with saline soaks. Antiseptics are avoided as they may retard granulation tissue formation and epitheliasation. Intractable or large ulcers may require skin grafts once the ulcer base is clean.
However the use of honey in the treatment of venous ulcers is now under investigation. Honey has numerous properties; it has a natural anti-inflammatory effect and also is a natural antiseptic. Honey has been shown to destroy many strains of bacteria including Staphylococcus, Streptococcus, Staphaureus and Helicobacter Pylori (offering a cure for millions of peptic ulcer sufferers). Consequently many types of bacteria cannot survive in honey, reducing the risk of infection and wound healing can take place.
The mode of application of honey varies. The most commonly reported procedure is to clean the site first with saline, spread honey on the wound and cover with a dry dressing, which is changed daily. Honey is hygroscopic (able to attract moisture). It draws moisture from the wound by osmosis forming a solution of honey that does not stick to the underlying tissue. This helps the dead tissue to separate and encourages growth of new granulation tissue. Honey dressings are therefore easy to apply and remove. Application of the dressing causes no pain, or only a minor stinging sensation. The dressing is non-irritating and causes no allergic reaction and has no harmful effects on tissues. Removal of the dressing has been shown to be relatively easy and non-painful with necrotic and gangrenous tissue being lifted off easily. There is no adhesion to the underlying granulation tissue and no bleeding when removing the dressings. The high osmolarity of honey induces outflow of lymph, which assists in lifting dirt and debris from the bed of the wound. Therefore dirt is removed with the bandage when honey is used as a dressing, leaving behind a clean wound. This cleansing effect makes surgical debridement unnecessary and saves the patient pain or risks associated with anaesthesia and surgery.
Clinically it has been recorded that honey quickly reduces inflammation, swelling and pain. Studies have shown that lesions treated with honey showed less oedema and fewer polymorphonuclear and mononuclear cell infiltrations. The sloughing of necrotic and gangrenous tissue is induced. Honey has been reported to promote the formation of clean healthy granulation tissue and epithelialisation of the wound. It is thought that honey has a direct nutrient effect on regenerating tissue as it contains a wide range of amino acids, vitamins and trace elements in addition to large quantities of sugar.
Experiments carried out on burns compared honey with a sugar solution of similar composition to honey. These showed that healing was more active and advanced with honey and the time taken for complete repair was significantly less. Honey resulted in a clearly seen attenuation of inflammation and exudation and a rapid regeneration of outer epithelial tissue. From this it was concluded that it is the chemical constitution rather than the physical properties of honey that are important.
In cases of infected wounds the use of honey has been shown to be very effective. The antimicrobial properties mentioned before prevent bacterial growth in the moist environment created. When using honey it may be necessary to warm it for easier application. However excessive heating should be avoided because the glucose oxidase enzyme in honey, which produces hydrogen peroxide, a major component of the antibacterial activity, is readily inactivated by heat. Reports show that honey is successful in cleaning up infected wounds with one study showing that wounds became sterile within one week using a honey dressing.
Honey dressings have also been shown to reduce odours from infected wounds. The high glucose levels that honey provides are used by the infected bacteria in preference to amino acids from the serum and dead cells. This gives rise to lactic acid instead of ammonia, amines and sulphur compounds that are the cause of malodour.
In the studies carried out, no adverse effects have been noted. Honey has been used topically on wounds for thousands of years without gaining a reputation for adverse effects and allergy to honey is rare. There is concern however that the high levels of glucose contained in honey may adversely elevate the blood glucose level of diabetics when applied topically on an open, large wound.
In conclusion it can be said that the use of honey should be realistically considered when treating venous ulcers. It provides a moist healing environment while preventing bacterial growth. It is effective in treating heavily infected wounds, making them sterile, without the side effects of antibiotics. It provides glucose to nourish leucocytes to drive the respiratory burst that produces hydrogen peroxide (the dominant component of the antibacterial activity of macrophages). Honey gives a fast rate of tissue regeneration and suppresses inflammation, oedema and malodour in wounds. The use of honey dressings results in better tissue organisation and consequently an improved tissue strength. All these findings suggest that honey when applied topically, is an ideal dressing for cutaneous wounds.