Herbal medicines interaction

Based on these reports, there are a growing number of reviews of herbal medicine interactions, which seek to prediet likely interactions based on the, often hypothesised, aetions of various herbs. Many of these predictions seem tenuous at best. 

Many of the interactions of herbal medicines (health foods, dietary supplements) with warfarin in the published Uterature are solely hypothetical based on the postulated pharmacological effects of known chemical constituents of the plants. These mechanisms are discussed further below. Where specific clinical data on a herbal medicine interaction with warfarin are available, this is covered in a separate monograph. 

GIT characteristics, either to improve or limit specific function, and thereby influence host health. However, the complex, multiple and varied nature of the combinations of phytochemicals present in plants and traditional herbal medicines has complicated efforts to better understand the specific interactions between phytochemicals and the GIT (Yuan and Lin, 2000). Phytochemicals have other applications, such as the use of guar gum as a vehicle to deliver therapeutics (Krishnaiah et al, 2001). 

Izzo, A. A. 8c Ernst, E. (2001). Interactions between herbal medicines and prescribed drugs a systematic review. Drugs, 61, 2163-75. 

Miller, L.G., Herbal medicinals Selected clinical considerations focusing on known or potential drug-herb interactions, Arch Intern Med, 158, 2200, 1998. 

This text is primarily aimed to benefit researchers and health care practitioners. Since health care practitioners find many of their patients using over-the-counter herbal medicines, they need a source to help them anticipate how these herbs will interact with their patients illnesses and... 

Conversely, active constituents may have cooperative effects and together act in an additive or synergistic (supra-additive) manner. In such cases, it would be better to consume the whole plant or extract, because the combination of constituents would give a greater effect than one alone. Thus, to blindly advocate either the use of whole herb or refined single constituents is naive. To fully know what is best for the desired effect, herbs must be considered on a case-by-case basis and the nature of the interactions between the chemical constituents must be carefully considered. Not only must we understand what the plant s chemical constituents do, we must also investigate how they interact. The Use of Herbal Medicine The Current Prevalence of Alternative Medicine... 

As already discussed, the same cannot be said for natural products used as dietary supplements. In most cases, those drugs have not heen subjected to the programs of testing required for FDA approval. As a result, products may pose a hazard to human health. Those hazards usually fall into one of four categories (1) the product may prevent a person from receiving other forms of FDA-approved medication that may he more beneficial to them (2) it may interact with other herbal medicines, prescribed drugs, and over-the-counter medications, with harmful effects (3) it may have no effect at all on a person s health or well-being or (4) it may actually cause harm to a person s health. 

Detractors of herbal medicine use have legitimate concerns about dosage variability, possible toxicity and adulteration, herb-drug interactions, and above all, lack of FDA regulation. Far from being intrinsically harmless, many pharmacologically active plant alkaloids and other compounds are natural defensive poisons their very effectiveness may be an unanticipated consequence of their adaptive toxicity to grazing animals and... 

D Arcy PF. Adverse reactions and interactions with herbal medicines. Part 2. Drug interactions. Adverse Drug React Toxicol Rev 1993 12 147-162. 

Ernst E. Herbal medicine where is the evidence BMJ 2000 321 395-396. Fugh-Berman A. Herb-drug interactions. Lancet 2000 355 134—138. 

Izzo A A, Di Carlo G, Borrelli F, Ernst E. Cardiovascular pharmacotherapy and herbal medicines the risk of drug interaction. Int J Cardiol 2005 98(1) 1-14. 

However, the information derived from a detailed pharmacokinetic study will help to anticipate potential botanical product-drug interactions, to optimize the bioavailability, the quality, and hence the efficacy of herbal medicines, to support evidence for the synergistic nature of herbal medicines, and to better appreciate the safety and toxicity of the plant. Because pharmacokinetic studies with herbal medicines are often complicated by their chemical complexity and by the fact that the active compounds are often unknown, it could be one future issue to assess bioavailability by measuring surrogate parameters in plasma or tissue instead of directly assaying putative active compounds in the blood. In summary, to use HMPs in an evidence-based approach and to achieve the status rational phytomedicine, more experimental studies are needed to characterize the bioavailability and pharmacokinetics of botanical products. 

Dergal JM et al Potential interactions between herbal medicines and conventional drug therapies used by older adults attending a memory clinic. Drugs Aging 2002 19 879. [PMID 12428996]... 

Continuing in the tradition of the acclaimed first edition. Pharmacodynamic Basis of Herbal Medicine, Second Edition examines in extensive detail the physiologic effects of complementary and alternative therapies, foods, supplements, vitamins, and traditional herbal remedies. This encyclopedic volume considers the site, mode, and mechanism of action to explain the desired and adverse effects and interactions of each herb, drug, and food. 

By deconstructing the molecular mystery that is the interaction among herbal properties, physiology, and disease, Pharmacodynamic Basis of Herbal Medicine, Second Edition opens the door to successful herbal treatment. 

This book summarizes current knowledge of the molecular basis of our interaction with plant defensive components that represents a major aspect of our dance with nature. However, knowledge must be used responsibly and has intrinsic dangers as illustrated in the ancient Greek myth of Pandora s box and as more recently explored in The Magic Mountain by Thomas Mann. Herbal medicine still represents a major therapeutic resort for a large part of humanity but the potential for deleterious effects of plant bioactive compounds means that expert medical advice should be sought before use of herbal extracts for medical conditions. 

Interactions of antidepressants with herbal medicines have been reported (53). Ginseng has been reported to cause mania, tremor, and headache when used in combination with conventional monoamine oxidase inhibitors. 

Herbal medicines are becoming more and more popular, and indeed some herbal products may be considered to benefit people with liver disease, e.g. Silybum marianum (milk thistle), Picrorhiza kurroa, Phyllanthus, etc. Herbal hepatotoxicity is increasingly being recognised, for example, with kava kava, black cohosh, and many traditional Chinese remedies. The range of liver injury includes minor transaminase elevations, acute and chronic hepatitis, steatosis, cholestasis, zonal or diffuse hepatic necrosis, veno-occlusive disease and acute liver failure. In addition to the potential for hepatotoxicity, herb-drug interactions may affect the safety and efficacy of concurrent medical therapy [15]. 

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