Herbs are potent substances that may contain chemicals that can interfere with the potency of medications that are prescribed by a doctor, or worse that may have side effects when used in conjunction with prescription drugs. This dilemma is heightened by the fact that both consumer and doctor alike may be unaware of potential complications from herbal supplements used in isolation for a condition, or in a combination with conventional medication (http://lib.bioinfo.pl/pmid:17425631, http://lib.bioinfo.pl/pmid:17691916).
To address concerns about possible side effects and drug interactions researchers are scrambling to determine exactly which herbs pose a danger to people currently on a regime of medications (, aafp.org/afp/990301ap/1239.html, http://lib.bioinfo.pl/pmid:18673195, hss.edu/conditions_14332.asp). Some herbs and medication interactions that are being investigated include;
*Goldenseal- Possibly affects drug levels in the body
*Chamomile and ciclosporin
* Kava- Sedatives, sleeping pills, anti-psychotics, alcohol
*Garlic- HIV medications, Blood thinner; don't use before surgery
* Echinacea- May trigger immunosuppression- Not Recommended for use after surgery
* St. John's wort- anticancer, anti-inflammatory, cardiovascular drugs, statins, contraceptive drugs , anti-depressants
* Gingko Biloba- anticoagulant drugs, aspirin, Coumadin (blood thinner)
*Ephedra- Caffeine, decongestants, stimulants
*Ginseng Warfarin
There is also reason for concern for people who are preparing to go under surgery. For instance, the American Society of Plastic Surgeons (ASPS) issued a report that suggested that many people who are using herbal supplements fail to discuss their use with the doctors before surgery increasing the risk of complications during surgery and afterwards in recovery (http://www.medicalnewstoday.com/articles/37731.php) .
National Center for Complementary and Alternative Medicine (NCCAM) Clearinghouse (http://www.hepfi.org/nnac/pdf/herbal.pdf) suggests that consumers be mindful of potential conflicts before taking prescribed medications, and to speak frankly with their physician before taking any supplements. Because herbal supplements don't require the approval of the FDA before going to market consumers must use caution, and read the labels of any products they are interested in taking. Things you can learn from the label include all the ingredients present in the formula, the amount of active ingredient, and dosing information. What you won't find on many labels, is the purity of the herbs listed, nor will you learn about possible drug interactions.
Certain populations are especially vulnerable to the use of herbal supplements. For example, pregnant woman should avoid the use of herbal supplements especially without the advice of her physician (http://www.hepfi.org/nnac/pdf/herbal.pdf). Other people who may have difficulty with specific herbs are people whose blood doesn't clot easily and the elderly (http://www.annalsoflongtermcare.com/content/use-her bal-medications-elderly-patients). Gingko bilboa and garlic both frequently used supplements that can lead to bleeding in this population.
There are many reasons to believe that herbal supplements can contribute to health, and to provide meaningful therapy for many conditions, however, it is important not to underestimate their potency, and to speak with your health care professional anytime a potential conflict between traditional or holistic medications and modern prescription drugs may arise.