Wednesday, 11 November 2015

Essay Report on the Efficacy and Safety of Herbal Medicine

Abstract

Herbal medicines are products originating from herbs which may have some ingredients with health benefits.  During recent years, there has been a dramatic increase in the use of herbal products as an alternative medicinal treatment around the world.  The efficacy and safety of using herbal medicinal products have been discussed for a long time.  The safety of herbal medicine is a complex issue interrelated to a variety of factors including methods of production, public perception, and attitudes with regards to the products, and the nature of the plants. There are many herbal medicines with the potential for toxicity and problems with contamination.  Furthermore, some herbal medicines may have particular side effects.  Another issue is that herbal medicine lacks a comprehensive, scientific universal standard.
Therefore, regulation of herbal medicine is required to assure consistency between studies and to develop the efficacy and safety of herbal drugs.

Introduction

Herbal medicines have been used for thousands of years.  In the last few decades, there has been significant growth in using herbal medicines, particularly in developed countries like Australia. This report highlights different aspects of herbal medicine including definition, the extent of use, safety and efficacy as well as the potential side effects and adverse reactions.

Description of Herbal Medicine

Herbal medicines are products originating from herb materials which may have health benefits. According to the World Health Organization (2000), ‘herbal materials include leaves, flowers, fruit, seed, stems, wood, bark, roots, and rhizomes’. Any of these given herb materials contain multiple ingredients which can be extracted in different forms like, fresh juices, gums, fixed oils, essential oils, resins, and dry powders.  The preparation of herbal medicine varies in different parts of the world. The production process may include steaming, roasting, stir baking with honey, alcoholic beverages or other materials, (WHO, 2000).

The Extent of Use of Herbal Medicine

The herbal medicine includes a significant proportion of alternative medicinal treatments around the world. As Chan (2003) mentions ‘around 70–8o percent of the world populations rely on non-conventional medicine mainly of herbal sources.’  Despite scientific improvements in conventional medicine and recent innovations in the sector of health services, data indicates a remarkable growth in using herbal medicine in developed countries.  ‘Nearly 1 in 5 adults in the United States report taking an herbal product’ (Bent, 2008). In other developed countries, the extent of use of herbal medicine is also quite high.  As Shaw (1998), states that ‘In 1994 the European herbal medicine market was worth over £1.8 billion at retail selling prices.’

Efficacy of Herbal Medicine

The efficacy of herbal medicinal products has been debated for quite a long time. Scientifically, the efficacy of any herbal remedy requires an evidence-based examination. Scientific examination of several herbal medicines and suggest that the following herbal medicines might have efficiency on specific health problems. Woolf (2003), states that the effectiveness of these three herbal medicines is scientifically approved in these particular treatments: Tea Tree Oil may be useful to remedying fungal skin disorders, Artemisia seems to be associated with chloroquine in the treatment of a specific kind of malaria, and St John’s Wort may help to treat mild depression in adults. Furthermore, according to Myers and Cheras (2004), garlic may reduce blood concentration; however, it may affect other conventional medicines like paracetamol and chlorpropamide. Although the efficacy of some herbal medicine has been examined, the effectiveness of other herbal medicine remains unverified, inadequately observed or not even examined at all.

Safety of Herbal Medicine

The safety of herbal medicine is a complex issue interrelated to different factors including public perception and the nature of plants. As Firenzuoli & Gori (2007) state, some herbal medicines have a foundation in magical or religious beliefs. Furthermore, according to Calixto (2000), most people think herbals are safe because they are natural substances. However, there are un-scientific perceptions and cultural superstitions with regards to using of herbal medicine, but the major circumstances by which the safety of herbal medicines could be affected include, but not limited to toxic hazards, side effects due to interaction with prescription medicine; lack of regulation of herbal medicine; and contamination, adulteration, and overdose usage.

·    Toxic Side Effects

There are many herbal medicines with the potential for toxicity. The degree of toxicity may vary in different herbal medicines. Furthermore, the toxic contaminants can originate from environmental situations as well as the periods and processes of preparation, storage and carriage, (Chan, 2003).  Even though some toxic herbals have been identified, many remain hazardous.  As Calixto (2000), has noted ‘since 1978, more than 4000 herbal medicines have been … marked out because of important toxic effects and risks for human use.’

·     Side Effects due to Interaction with Prescription Drug

There are particular side effects for some kind of herbal medicine. ‘Although herbs are often perceived as “natural” and therefore safe, many different side effects have been reported owing to active ingredients, contaminants, or interactions with drugs’ (Bent, 2008).  According to Ekor (2014), the ordinary side effects associated with Kava vary from headache and dizziness to gastrointestinal discomfort and redness of the eyes.  Even though, side effects may be inherent in some herbal medicine, when taken with prescription drugs there may be serious side effects. In addition, due to the non-prescription availability of herbal medicine, the potential risks of interaction with other drugs, is quite difficult to be documented.  Myers and Cheras (2004) state that patients often do not advise their doctors that they are using herbal products and when combined with prescription medicines the effect can be serious.

·    Regulation of Herbal Medicine

Regulation of herbal medicine is required to assure consistency between studies and to ensure the efficacy and safety of herbal drugs. Regulation of herbal medicine differs based on regions and countries in the world. ‘Several regulatory models for herbal medicines currently exist (Calixto, 2000). In many countries including the United States herbal medicines are sold as a dietary supplement and there is no regulation, while in some other countries like the UK, drug regulations are applicable to some specific kind of herbals products. Global harmonization is essential to assure the efficacy and safety of herbal medicine, which will be achieved through well-controlled and randomized clinical trials and regulation processes (Calixto, 2000).   

·      Contaminated and Adulteration

Herbal medicine can be contaminated in a variety of ways. Primarily contamination accrues during the preparation of herbal medicine, though, contamination can happen in the periods of storage (Shaw, 1998).  The intentional accumulation of extra ingredients with herbal medicine is called adulteration, in which a safe herb may be substituted with a wrong constituent. Contamination and adulteration are potential factors for either study interference in research or serious health effects for patients. Furthermore, there are herbal products which are deliberately manipulated with the purpose of boosting its efficacy. This herbal process is called adulteration. ‘Adulteration complicates adverse reaction monitoring since the wrong plant may be investigated, and documented effects may be associated with the wrong herb, (Shaw, 1998). 

·     Toxicity by heavy metals

Toxicity can be caused by a higher concentration of heavy metals. According to Singh, et al (2011) “Prolonged exposure to heavy metals such as cadmium, copper, lead, nickel, and zinc can cause deleterious health effects in humans. Molecular understanding of plant metal accumulation has numerous biotechnological implications also, the long term effects of which might not be yet known.”

Conclusion

There has been a long history of using herbal medicine, yet, the efficacy and safety of many herbal medicines remain experimental. Even though, a variety of side effects, either intrinsic or extrinsic have been observed, herbal medicine seems to be beneficial for health. Therefore, further research to assess the the efficacy and safety of herbal product is required.   

Recommendations

·       Governments and related institutions should launch a strategic work plan to ensure local regulation of herbal medicine leading to global and international standardization. 
·       Related institutions along with governments should work to raise public awareness regarding the risks and side effects of natural retrieved drugs particularly herbal medicine. This requires a cumulative public awareness campaign, targeting the misperceptions of using herbal medicine, emphasizing neither every natural substance is safe nor every cultural attitude is accurate.  
·       Manufacturers should feature the major side effects on every individual herbal medicine packaging.
·       Further studies and research need to be done aiming not only to find the positive aspects but also investigate side effects of herbal medicine.  In order to conduct further research studies, government should raise funding in this field. 

Acknowledgment

The writer gratefully acknowledges the support provided by the writing teacher, Jenny Parry during the course of preparation of this report.

Reference List

Bent, S. (2008). Herbal medicine in the United States: Review of efficacy, safety, and regulation. Journal of General Internal Medicine, 23 (6). 854-859. doi:10.1007/s11606-008-0632-y.  

Calixto, J. B. (2000). Efficacy, safety, quality control, marketing and regulatory guidelines for herbal medicines (Phytotherapeutic agents). Brazilian Journal of Medical and Biological Research, 33(2),179-189. Retrieved from: http://dx.doi.org/10.1590/S0100-879X2000000200004

Chan, K. (2003). Review Some aspects of toxic contaminants in herbal medicines. Chemosphere, 52. p.1361–1371. Retrieved from: http://faculty.ksu.edu.sa/alqasoumi/Documents/Some%20aspects%20of%20toxic%20contaminants%20in%20herbal%20medicines.pdf

Ekor, M. (2014) The growing use of herbal medicines: issues relating to adverse reactions and challenges in monitoring safety. Frontiers in Pharmacology, 4. doi: 10.3389/fphar.2013.00177

Firenzuoli, F., and Gori, L. (2007). Herbal medicine today: clinical and research issues. Evidence-Based Complementary and Alternative Medicine, 4(1), 37–40. Retrieved from doi: 10.1093/ecam/nem096 

Myers, S.P. and Cheras, P.A. (2004) The other side of the coin: safety of complementary and alternative medicine. Medical Journal of Australia 181(4),222-225.

Shaw, D. (1998) Risks or remedies? safety aspects of herbal remedies in the UK.  Journal of the Royal Society of Medicine, 91, 294-296. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1296770/pdf/jrsocmed00024-0008.pdf

Woolf, A, D. (2003) Herbal remedies and children: Do they work? are they harmful? the American Academy of Pediatrics. 112:240. Retrieved from: http://pediatrics.aappublications.org/content/112/Supplement_1/240.full.html#ref-list-1


World Health Organization. (2000). General guidelines for methodologies on research and evaluation of traditional medicine, (1), p.3. Retrieved from: http://apps.who.int/iris/bitstream/10665/66783/1/WHO_EDM_TRM_2000.1.pdf

2 comments: