Herbal supplement

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Humans have used botanicals for medicinal purposes as far back as archeaologic evidence exists.  About 30% of all FDA-approved drugs are derived from botanical sources.<ref>Sardesai, Vishwanath M. Herbal medicines: poisons or potions?. Journal of Laboratory & Clinical Medicine. 139(6):343-8, 2002 Jun.</ref>  Examples include aspirin (from willow bark) and digoxin (from the foxglove plant).  [[Molecular biology]] has allowed for more directed drug development.  For instance, the active ingredient in a plant extract can be identified, isolated, and replicated.  The molecule can also be modified to add desired effects or eliminate undesired effects.  Sometimes molecules are altered in order to develop a drug just different enough from the old medication to allow a new patent to be issued.  "Reverse" development is also done, where a receptor in the body is identified, and computers assist in identifying molecules to fit these receptors.  In sum, many modern medicines started as plant extracts and were refined to improve the medicinal characteristics, including reducing toxicity.
 
Humans have used botanicals for medicinal purposes as far back as archeaologic evidence exists.  About 30% of all FDA-approved drugs are derived from botanical sources.<ref>Sardesai, Vishwanath M. Herbal medicines: poisons or potions?. Journal of Laboratory & Clinical Medicine. 139(6):343-8, 2002 Jun.</ref>  Examples include aspirin (from willow bark) and digoxin (from the foxglove plant).  [[Molecular biology]] has allowed for more directed drug development.  For instance, the active ingredient in a plant extract can be identified, isolated, and replicated.  The molecule can also be modified to add desired effects or eliminate undesired effects.  Sometimes molecules are altered in order to develop a drug just different enough from the old medication to allow a new patent to be issued.  "Reverse" development is also done, where a receptor in the body is identified, and computers assist in identifying molecules to fit these receptors.  In sum, many modern medicines started as plant extracts and were refined to improve the medicinal characteristics, including reducing toxicity.
  
Currently, approximately 12-25% of Americans use an herbal remedy yearly.<ref>Bent, Stephen. Ko, Richard. Commonly used herbal medicines in the United States: a review. American Journal of Medicine. 116(7):478-85, 2004 Apr 1.</ref> Despite their popularity, these substances, advertised as medically active, are regulated as dietary supplements, rather than as medicines by the FDA.  This means that there is very little regulation about manufacturing or content of these substances.
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Currently, approximately 12-25% of Americans use an herbal remedy yearly.<ref>Bent, Stephen. Ko, Richard. Commonly used herbal medicines in the United States: a review. American Journal of Medicine. 116(7):478-85, 2004 Apr 1.</ref> Despite their popularity, these substances, advertised as medically active, are regulated as dietary supplements, rather than as medicines by the FDA.  This means that there is very little regulation about manufacturing or content of these substances. In Canada every natural product must apply for a natural product number (NPN) and are now governed under the ''[http://laws.justice.gc.ca/en/F-27/SOR-2003-196/ Natural Health Product Regulations]'', which include provisions on adverse reaction reporting, labelling, and site and product licencing.<ref>About Natural Health Product Regulations; Health Canada webiste</ref>
  
 
Americans, however, often perceive herbals as "safer", "more natural", and "more [[holistic]]" than conventional medications.  Also, many are suspicious of the profit motive of the pharmaceutical industry.  Herbal medications do, of course, represent an enormous financial interest.  Echinacea alone has annual sales of about 300 million dollars in the U.S.<ref>Bent, Stephen. Ko, Richard. Commonly used herbal medicines in the United States: a review. American Journal of Medicine. 116(7):478-85, 2004 Apr 1.</ref>
 
Americans, however, often perceive herbals as "safer", "more natural", and "more [[holistic]]" than conventional medications.  Also, many are suspicious of the profit motive of the pharmaceutical industry.  Herbal medications do, of course, represent an enormous financial interest.  Echinacea alone has annual sales of about 300 million dollars in the U.S.<ref>Bent, Stephen. Ko, Richard. Commonly used herbal medicines in the United States: a review. American Journal of Medicine. 116(7):478-85, 2004 Apr 1.</ref>

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Herbal supplements are non-pharmaceutical, non-food substances marketed to improve health. Herbalism (herbal medicine, botanical medicine) is the use of plant-derived substances, and sometimes other environmental substances, to treat or cure medical conditions. Herbalism recognizes that pre-industrial cultures had a great deal of practical medical knowledge, most of it botanical, and seeks to make use of this. Definitions are problematic. There is no unified practice, and no guidelines for practitioners. Also, there is no clear definition of an "herbal remedy". A large number of currently available drugs are originally plant-derived.

Contents

History

Humans have used botanicals for medicinal purposes as far back as archeaologic evidence exists. About 30% of all FDA-approved drugs are derived from botanical sources.[1] Examples include aspirin (from willow bark) and digoxin (from the foxglove plant). Molecular biology has allowed for more directed drug development. For instance, the active ingredient in a plant extract can be identified, isolated, and replicated. The molecule can also be modified to add desired effects or eliminate undesired effects. Sometimes molecules are altered in order to develop a drug just different enough from the old medication to allow a new patent to be issued. "Reverse" development is also done, where a receptor in the body is identified, and computers assist in identifying molecules to fit these receptors. In sum, many modern medicines started as plant extracts and were refined to improve the medicinal characteristics, including reducing toxicity.

Currently, approximately 12-25% of Americans use an herbal remedy yearly.[2] Despite their popularity, these substances, advertised as medically active, are regulated as dietary supplements, rather than as medicines by the FDA. This means that there is very little regulation about manufacturing or content of these substances. In Canada every natural product must apply for a natural product number (NPN) and are now governed under the Natural Health Product Regulations, which include provisions on adverse reaction reporting, labelling, and site and product licencing.[3]

Americans, however, often perceive herbals as "safer", "more natural", and "more holistic" than conventional medications. Also, many are suspicious of the profit motive of the pharmaceutical industry. Herbal medications do, of course, represent an enormous financial interest. Echinacea alone has annual sales of about 300 million dollars in the U.S.[4]

Effectiveness

Many studies have been done of herbal medications. Unfortunately they often lack good documentation, quality, and suffer from not having analyzed the substance studied. [5][6] Because of the lack of quality control and regulation, it is difficult to assess what the effect of many herbs is, or even what people may be taking, given the label often fails to match the content.

Given these limitations, a summary of studies of some popular supplements is listed below:[7]

  • Ginkgo is sold as a "memory aid" and a treatment for Alzheimer's disease. Studies have show mixed results, with a possibility of it being better than placebo.
  • Saw palmetto: marketed as a treatment for benign prostate disease in men, studies show some effect greater than placebo, at least in the short term.
  • St. John's Wort: used for depression, data show short-term efficacy over placebo for mild to moderate depression.
  • Ginseng: many different types, insufficient data exist.
  • Echinacea: marketed for the common cold, no good, consistent studies have been done.
  • Evening primrose oil: for PMS, studies show no benefit
  • Ginger: insufficient data
  • Garlic: insufficient data
  • Kava: marketed for anxiety, some improvement over placebo, side effects.
  • Valerian root: for insomnia: data are inconclusive.

Potential Harms

Much of the time, herbal remedies are used without consulting a physician about the condition in question. This may lead to delay or failure of diagnosis of important medical conditions. For example, a man who takes saw palmetto for his urinary problems may have all the signs and symptoms of prostate cancer, but if he may not be diagnosed until it is too advanced for treatment. Herbs can also interfere with conventional medications.

As herbs have become more popular, and as more have become available with globalization, more toxic effects are being seen. Herbal preparations may or may not resemble the traditional cure from which it was derived, and are often used in a different context. For instance, small amounts of Mahuang may exist in certain Chinese medicines, but is used in much higher concentrations in the West. Many common herbs can be quite toxic, and may exist in supplements without clear labeling. For example, Mahuang can cause serious cardiac disturbances and Kava can injure the liver. New reports come out regularly about liver failure caused by herbal remedies. Herbal remedies from outside the U.S. are sometimes contaminated with lead and other heavy metals.

Summary

Many herbal remedies have significant medical effects. Labeling may not correctly describe the contents of the medication. The preparations available are not well-regulated or well-studied. As such, they are often wasteful, or even toxic. When there is a measurable effect, it is often more modest than the available conventional medicines.[8] Many companies are doing large scale testing of botanicals to look for biologically active substances. Older remedies, and new ones, as discovered, should be subject to the same scrutiny as any other medication. There is no reason to believe that herbal remedies have any "natural" advantage over conventional ones. Randomized controlled trials can distinguish good medicines from bad, independent of the source.

References

  1. Sardesai, Vishwanath M. Herbal medicines: poisons or potions?. Journal of Laboratory & Clinical Medicine. 139(6):343-8, 2002 Jun.
  2. Bent, Stephen. Ko, Richard. Commonly used herbal medicines in the United States: a review. American Journal of Medicine. 116(7):478-85, 2004 Apr 1.
  3. About Natural Health Product Regulations; Health Canada webiste
  4. Bent, Stephen. Ko, Richard. Commonly used herbal medicines in the United States: a review. American Journal of Medicine. 116(7):478-85, 2004 Apr 1.
  5. Gagnier, Joel J. DeMelo, Jaime. Boon, Heather. Rochon, Paula. Bombardier, Claire. Quality of reporting of randomized controlled trials of herbal medicine interventions. American Journal of Medicine. 119(9):800.e1-11, 2006 Sep.
  6. Wolsko, Peter M. Solondz, David K. Phillips, Russell S. Schachter, Steven C. Eisenberg, David M. Lack of herbal supplement characterization in published randomized controlled trials. American Journal of Medicine. 118(10):1087-93, 2005 Oct.
  7. De Smet, Peter A G M. Institution. Herbal remedies. New England Journal of Medicine. 347(25):2046-56, 2002 Dec 19.
  8. Koretz, Ronald L. Is alternative medicine alternative science? Journal of Laboratory & Clinical Medicine. 139(6):329-33, 2002 Jun.
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