Executive Summary
Honey is a carbohydrate-rich syrup produced by bees, primarily from floral nectars. Fructose and glucose are the major components but a large number of other chemical compounds are present in small quantities. Moisture content and water activity are low. The British Pharmacopeia (1993) provides a monograph for purified honey.
Four aspects of the composition of honey have been identified to contribute to its antibacterial activity. The low water activity inhibits microbial growth, particularly bacterial growth. Its low pH, a result of the formation of gluconic acid, also has a mild antibacterial effect. When diluted with water, hydrogen peroxide is formed by the action of the enzyme glucose oxidase. Finally, some honeys contain other compounds, largely uncharacterised, that have antimicrobial activity.
Antibacterial activity can be easily measured in vitro, by the use of established microbiological techniques, such as agar well diffusion assays. Studies using this, and other related techniques, have shown that antimicrobial activity varies widely according to the source of the honey, but that most honeys have significant activity against a range of pathogens. These pathogens include those commonly implicated in gastric and skin ulcers.
A number of studies have been carried out on animal models of wound and burn healing in which honey is used as a treatment. These studies compare the use of topical honey to other treatments including saline and silver sulfadiazine.
Honey has an extensive history of traditional human medicinal use, in a large number of societies. It may be used alone or in combination with other substances, and has been administered both orally and topically.
The few clinical trials of honey in human therapeutic use are summarised. These studies evaluated the use of honey to treat partial thickness burns to less than 40% of the body surface area and compared honey to other treatments such as sterile gauze, silver sulfadiazine, amniotic membrane and boiled potato skins. Honey compared favourably to these treatments, in terms of reducing healing time and in limiting infections during healing.
There are a considerable number of clinical reports of the use of honey to treat ulcers, burns, surgical wounds and gastric ulcers and as a carbohydrate source in oral rehydration therapy. Many of these studies showed beneficial effects of honey use.
As a widely consumed food, honey has a very long history of safe use, its low water activity protecting it from microbial spoilage. The majority of clinical reports of honey use indicate few if any adverse effects, the most common complaint being a burning sensation with topical application. ADRAC has no adverse reports associated with honey. Nevertheless there are three areas of potential safety risk associated with honey: toxic honey, allergy to honey, and infant botulism. Production of toxic honey is controlled largely through limiting honey production from areas where toxic honey has been produced in the past, and through blending different batches of honeys. Honey allergy is not common but is well recognised and can result in anaphylaxis. Allergy may be to both plant and bee proteins found in the honey. Infant botulism is a rare condition caused by contamination of honey with spores of Clostridia. Australian health authorities recommend that honey not be eaten by infants.
Assessment
Honey is a substance with a long history of traditional use as an active medicinal compound. In modern pharmaceutical practice it is widely used as an excipient ingredient and a monograph exists in the BP93 that adequately defines the substance and is already used by the TGA for this purpose.
The mechanism of antimicrobial action of honey is most likely a combination of a number of different factors. Its low water activity is likely to play a major role when honey is applied topically, but studies comparing its effect to sugar syrups of the same concentration have shown that honey has superior activity. Hydrogen peroxide is produced within honey by the
action of the bee-derived enzyme glucose oxidase and has known antimicrobial activity.
Chromatographic studies have shown that honey contains a wide range of compounds, many of which have not been identified. In some honeys such as manuka honey, removal of peroxide does not destroy all antimicrobial activity, suggesting that some other compounds in honey also play a role in inhibiting microbial growth.
There are many reports of the traditional medicinal use of honey in a large number of cultures. Both the Bible and the Koran recommend its use. It has been used in a wide range of conditions, including skin, eye, respiratory and gastrointestinal illnesses.
Animal studies have shown that topically-applied honey can be effective in accelerating wound healing and in controlling infection in wounds in some circumstances. The number of animal studies is small and several of these are poorly designed and have major inadequacies in result reporting. For example, authors generally do not indicate the severity of the wounds
applied to test animals, making it difficult to extrapolate the findings to wounds observed in humans. Poor design and reporting limit the worth of two animal studies supplied in the application of the use of honey to treat experimentally-induced gastric ulcers.
Human clinical trials of honey use are scarce. One Indian researcher has conducted a number of trials of the use of topically-applied honey in patients (50 to 100 per trial) with partial thickness burns covering less than 40% of their body surface area. The trials compared honey to a range of modern and traditional remedies, with patients randomly assigned to treatments. Honey treatment was more effective than sterile gauze/film, silver sulfadiazine, potato skins and amniotic membrane, with more rapid healing, fewer infections and some evidence of reduced inflammation in healing tissue.
There are a considerable number of observations in the medical literature of the use of honey to treat human burns, ulcers and surgical wounds. Most of these reports are of honey’s use in developing countries, where it provides major advantages in terms of its low cost and ease of use. Many of the wounds treated had already been treated conventionally with little success
and within this context, honey was found to be an effective treatment in accelerating healing and reducing the incidence of infection. However one study of long-standing leg ulcers, predominantly varicose ulcers, found that honey had limited efficacy.
Incomplete information suggests that honey has the potential to be incorporated into products used for skin infections, gastrointestinal conditions, eye infections and to treat nappy rash. Only one study is provided to support the use of honey to treat gastric ulcers. This study is
poorly designed and reported and little weight can be given to its findings, which claimed that honey was an effective treatment in cases of moderate-severe ulceration. Similarly, the only study examining honey for opthalmic use is also poorly designed and of little use. There is no evidence presented to support the use of honey in nappy rash ointments, although the studies of honey and skin ulcers suggest that honey may be effective for the treatment of minor rashes.
This paper is an evaluation of the safety of honey for use in listable medicines. These medicines must only be used for minor, self-limiting conditions and promoted in accordance with the Therapeutic Goods Advertising Code. Ointment style products for the treatment of
minor cuts and burns, and oral products for the relief of symptoms of indigestion are the types of products that would be acceptable as listable goods. If sponsors wished to produce goods to treat conditions such as varicose or gastric ulcers, Registration would be required and sponsors would be required to produce evidence of efficacy. The evidence presented in this paper would be insufficient to establish efficacy for uses such as gastric ulcer treatment.
Honey was incorporated into an oral rehydration solution and compared to the standard World Health Organisation (WHO) solution in the treatment of dehydrated infants. The honey solution was of comparable efficacy to the standard treatment. Oral rehydration products must undergo Registration and therefore any honey-containing products proposed for use would undergo thorough evaluation of efficacy and label claims. The evidence
presented in this paper would be insufficient to establish efficacy or safety for oral rehydration products.
Oral rehydration products are generally targeted to infants and young children as these are two of the population groups most susceptible to the effects of dehydration. However honey has been known to induce infantile botulism as a result of the presence of spores of Clostridia. For this reason, honey is not recommended for use as a food for infants in Australia. Any listable goods containing honey and recommended for oral use should be
required to carry a warning that they are not suitable for use by infants without medical supervision.
Allergy to honey is known to occur and can result in anaphylaxis, although such allergic reactions are not common. One source suggests that approximately 2% of people with food allergies may be allergic to honey. The allergenic components in honey may be derived from either bee or plant proteins. When presented as a food, honey is not required to carry a
warning statement about allergenic potential. There is no evidence available in Australia to indicate that any therapeutic goods containing honey have caused severe allergic reactions.
Honey can contain toxic compounds when produced by bees foraging on toxic plants or on the poisonous nectar produced by some sap-sucking insects. Deaths from toxic honey consumption have been recorded throughout history. This problem is generally controlled by prohibiting honey production in certain areas and by blending different batches of honey to
reduce concentrations of any particular toxins that may be present.
Conclusion
Honey is a substance suitable for use as an active ingredient in listable therapeutic goods in Australia. It is likely to find use in products such as ointments for the treatment of minor burns, cuts and skin infections. While it may be suitable for use in oral rehydration products and to treat more severe burns and wounds, such treatment would require medical supervision
and products for these uses would require Registration.
Honey is a carbohydrate-rich syrup produced by bees, primarily from floral nectars. Fructose and glucose are the major components but a large number of other chemical compounds are present in small quantities. Moisture content and water activity are low. The British Pharmacopeia (1993) provides a monograph for purified honey.
Four aspects of the composition of honey have been identified to contribute to its antibacterial activity. The low water activity inhibits microbial growth, particularly bacterial growth. Its low pH, a result of the formation of gluconic acid, also has a mild antibacterial effect. When diluted with water, hydrogen peroxide is formed by the action of the enzyme glucose oxidase. Finally, some honeys contain other compounds, largely uncharacterised, that have antimicrobial activity.
Antibacterial activity can be easily measured in vitro, by the use of established microbiological techniques, such as agar well diffusion assays. Studies using this, and other related techniques, have shown that antimicrobial activity varies widely according to the source of the honey, but that most honeys have significant activity against a range of pathogens. These pathogens include those commonly implicated in gastric and skin ulcers.
A number of studies have been carried out on animal models of wound and burn healing in which honey is used as a treatment. These studies compare the use of topical honey to other treatments including saline and silver sulfadiazine.
Honey has an extensive history of traditional human medicinal use, in a large number of societies. It may be used alone or in combination with other substances, and has been administered both orally and topically.
The few clinical trials of honey in human therapeutic use are summarised. These studies evaluated the use of honey to treat partial thickness burns to less than 40% of the body surface area and compared honey to other treatments such as sterile gauze, silver sulfadiazine, amniotic membrane and boiled potato skins. Honey compared favourably to these treatments, in terms of reducing healing time and in limiting infections during healing.
There are a considerable number of clinical reports of the use of honey to treat ulcers, burns, surgical wounds and gastric ulcers and as a carbohydrate source in oral rehydration therapy. Many of these studies showed beneficial effects of honey use.
As a widely consumed food, honey has a very long history of safe use, its low water activity protecting it from microbial spoilage. The majority of clinical reports of honey use indicate few if any adverse effects, the most common complaint being a burning sensation with topical application. ADRAC has no adverse reports associated with honey. Nevertheless there are three areas of potential safety risk associated with honey: toxic honey, allergy to honey, and infant botulism. Production of toxic honey is controlled largely through limiting honey production from areas where toxic honey has been produced in the past, and through blending different batches of honeys. Honey allergy is not common but is well recognised and can result in anaphylaxis. Allergy may be to both plant and bee proteins found in the honey. Infant botulism is a rare condition caused by contamination of honey with spores of Clostridia. Australian health authorities recommend that honey not be eaten by infants.
Assessment
Honey is a substance with a long history of traditional use as an active medicinal compound. In modern pharmaceutical practice it is widely used as an excipient ingredient and a monograph exists in the BP93 that adequately defines the substance and is already used by the TGA for this purpose.
The mechanism of antimicrobial action of honey is most likely a combination of a number of different factors. Its low water activity is likely to play a major role when honey is applied topically, but studies comparing its effect to sugar syrups of the same concentration have shown that honey has superior activity. Hydrogen peroxide is produced within honey by the
action of the bee-derived enzyme glucose oxidase and has known antimicrobial activity.
Chromatographic studies have shown that honey contains a wide range of compounds, many of which have not been identified. In some honeys such as manuka honey, removal of peroxide does not destroy all antimicrobial activity, suggesting that some other compounds in honey also play a role in inhibiting microbial growth.
There are many reports of the traditional medicinal use of honey in a large number of cultures. Both the Bible and the Koran recommend its use. It has been used in a wide range of conditions, including skin, eye, respiratory and gastrointestinal illnesses.
Animal studies have shown that topically-applied honey can be effective in accelerating wound healing and in controlling infection in wounds in some circumstances. The number of animal studies is small and several of these are poorly designed and have major inadequacies in result reporting. For example, authors generally do not indicate the severity of the wounds
applied to test animals, making it difficult to extrapolate the findings to wounds observed in humans. Poor design and reporting limit the worth of two animal studies supplied in the application of the use of honey to treat experimentally-induced gastric ulcers.
Human clinical trials of honey use are scarce. One Indian researcher has conducted a number of trials of the use of topically-applied honey in patients (50 to 100 per trial) with partial thickness burns covering less than 40% of their body surface area. The trials compared honey to a range of modern and traditional remedies, with patients randomly assigned to treatments. Honey treatment was more effective than sterile gauze/film, silver sulfadiazine, potato skins and amniotic membrane, with more rapid healing, fewer infections and some evidence of reduced inflammation in healing tissue.
There are a considerable number of observations in the medical literature of the use of honey to treat human burns, ulcers and surgical wounds. Most of these reports are of honey’s use in developing countries, where it provides major advantages in terms of its low cost and ease of use. Many of the wounds treated had already been treated conventionally with little success
and within this context, honey was found to be an effective treatment in accelerating healing and reducing the incidence of infection. However one study of long-standing leg ulcers, predominantly varicose ulcers, found that honey had limited efficacy.
Incomplete information suggests that honey has the potential to be incorporated into products used for skin infections, gastrointestinal conditions, eye infections and to treat nappy rash. Only one study is provided to support the use of honey to treat gastric ulcers. This study is
poorly designed and reported and little weight can be given to its findings, which claimed that honey was an effective treatment in cases of moderate-severe ulceration. Similarly, the only study examining honey for opthalmic use is also poorly designed and of little use. There is no evidence presented to support the use of honey in nappy rash ointments, although the studies of honey and skin ulcers suggest that honey may be effective for the treatment of minor rashes.
This paper is an evaluation of the safety of honey for use in listable medicines. These medicines must only be used for minor, self-limiting conditions and promoted in accordance with the Therapeutic Goods Advertising Code. Ointment style products for the treatment of
minor cuts and burns, and oral products for the relief of symptoms of indigestion are the types of products that would be acceptable as listable goods. If sponsors wished to produce goods to treat conditions such as varicose or gastric ulcers, Registration would be required and sponsors would be required to produce evidence of efficacy. The evidence presented in this paper would be insufficient to establish efficacy for uses such as gastric ulcer treatment.
Honey was incorporated into an oral rehydration solution and compared to the standard World Health Organisation (WHO) solution in the treatment of dehydrated infants. The honey solution was of comparable efficacy to the standard treatment. Oral rehydration products must undergo Registration and therefore any honey-containing products proposed for use would undergo thorough evaluation of efficacy and label claims. The evidence
presented in this paper would be insufficient to establish efficacy or safety for oral rehydration products.
Oral rehydration products are generally targeted to infants and young children as these are two of the population groups most susceptible to the effects of dehydration. However honey has been known to induce infantile botulism as a result of the presence of spores of Clostridia. For this reason, honey is not recommended for use as a food for infants in Australia. Any listable goods containing honey and recommended for oral use should be
required to carry a warning that they are not suitable for use by infants without medical supervision.
Allergy to honey is known to occur and can result in anaphylaxis, although such allergic reactions are not common. One source suggests that approximately 2% of people with food allergies may be allergic to honey. The allergenic components in honey may be derived from either bee or plant proteins. When presented as a food, honey is not required to carry a
warning statement about allergenic potential. There is no evidence available in Australia to indicate that any therapeutic goods containing honey have caused severe allergic reactions.
Honey can contain toxic compounds when produced by bees foraging on toxic plants or on the poisonous nectar produced by some sap-sucking insects. Deaths from toxic honey consumption have been recorded throughout history. This problem is generally controlled by prohibiting honey production in certain areas and by blending different batches of honey to
reduce concentrations of any particular toxins that may be present.
Conclusion
Honey is a substance suitable for use as an active ingredient in listable therapeutic goods in Australia. It is likely to find use in products such as ointments for the treatment of minor burns, cuts and skin infections. While it may be suitable for use in oral rehydration products and to treat more severe burns and wounds, such treatment would require medical supervision
and products for these uses would require Registration.