Bibliography on Herb-Drug and Food-Drug Interactions

 

Kathrin Hohl and Wilhelm Gaus

Department of Biometry and Medical Documentation, University of Ulm, Ulm, Germany

 

 

Table of Contents

Objective

Coverage of bibliography

Components of bibliography

Available Information

Classification of study types

Remedies (herbs and foods)

Structure of article identification

Chemically defined drugs

Authors

Examples of use

 

Provided files: Main File, Index of Investigated Herbs and Foods, Index of Investigated Chemically Defined Drugs, Index of Authors

Print or download files as PDF: Main File (PDF), Index of Investigated Herbs and Foods (PDF), Index of Investigated Chemically Defined Drugs (PDF),

 Index of Authors (PDF)

 

 



 

 

 

Objective

The objective of this bibliography was to consolidate the clinical aspects of interactions between herbal remedies and foods on one hand side and chemically defined drugs on the other side. Literature was retrieved by extended searches in a variety of electronic databases and hand-searched references in articles. Further, we received articles from the German drug authority BfArM and members of the BfArM’s Commision E responsible for phytotherapy. The search was constrained to publications between January 1989 and June 2004.

 

 

Coverage of bibliography

Overall, 175 articles were included in the bibliography. They deal with 55 different herbs and foods and 102 different chemically defined drugs. Saint John’s wort is the most detailed investigated herb and grapefruit the most detailed investigated food involved in interactions with chemically defined drugs. This bibliography covers 31 (18%) overviews, 36 (21%) randomized controlled trials, 36 (21%) non randomized studies, 27 (15%) case reports, 13 (7%) animal experiments, 9 (5%) in vitro experiments and 23 (13%) personal opinions. Most interactions described were pharmacokinetic. In this bibliography 20 articles are included, which only investigated the effect of herbs or foods on cytochrome P 450 activity. An induction or inhibition of this activity by a herb or food may cause an interaction with a chemically defined drug.

 

 

 

Components of the bibliography

The bibliography consists of a main file, an index of investigated herbs and foods, an index of investigated chemically defined drugs and an index of authors. In the main file each article is classified under the aspects (i) specific herb or food, (ii) type of study, (iii) chemically defined drug(s), (iv) investigated subjects and sample size, (v) main clinical results and (vi) some comments. Finally, full bibliographical reference is given. Unfortunately, we were not allowed to include the abstracts of the referenced articles due to copyright protection.

 

 

 

Available information

The main file provides full information. It is sorted by the preferred term of herbs and foods. Overviews and personal opinions are exceptions, since mostly they cover several remedies. Overviews are at the very beginning and personal opinions are at the very end of the main file. Within overviews and within personal opinions the sequence is sorted chronologically by year of publication and within a year by name of first author. Within a certain herb or within a certain food the articles are sorted by type of study in the following order: randomized controlled trials, non randomized studies, case reports, animal experiments, and in vitro experiments. Within one type of study the articles are sorted by year of publication and within a year by name of first author. 

 

 

 

Classification of study types

The following abbreviations for the different study types are used as part of the article identification:

   R = Randomized controlled trial

   N = Non randomized study

   C = Case report

   A = Animal experiment

   V = in Vitro experiment

 

 

 

Remedies (herbs and foods)

As mentioned above, the main file is sorted by the preferred term, which is mostly the English, not the Latin name of the remedy. The index of investigated herbs and foods includes the preferred terms as well as non-preferred terms. Further, it specifies for preferred terms a unique label consisting of 3 letters. The label is used as an abbreviation of the remedy in the main file and is part of the article identification. 

 

 

 

Structure of article identification

Article identifications consist predominantly of 3 letters (the label of the herb or food supplement), a period, another letter indicating the type of study and a 2 digit sequential number with low numbers representing most recent publications. 

Example:         

image1

The two exceptions of the structure of article identifications are those for overviews and personal opinions. They consist of 2 letters (OV or PO respectively) and a 2 digit sequential number.

Examples:       

image2

 

 

 

Chemically defined drugs

The index of investigated chemically defined drugs lists all chemically defined drugs involved in interactions and the corresponding article identifications. The drugs are sorted in therapeutic groups according to the German drug register called “Rote Liste”. The two exceptions of this index: alcohol and caffeine are listed at the beginning.

 

 

 

Authors

The index of authors lists all first and co-authors and the corresponding article identification(s). Bold names are first authors, others are co-authors. Similarly, bold article identifications represent articles with the author being first author, others represent articles, where the author was a co-author.

 

 

 

Examples of use

1.    Search for articles regarding a specific herb or food involved in chemically defined drug interaction, knowing the preferred term (mostly English name) of the remedy:

You can find those articles in the main file searching for the preferred term (skipping the overviews at the very beginning). After the preferred term all articles primarily regarding this remedy are listed. At the end of the paragraph article identifications of overviews, articles primarily concerning another remedy and personal opinions are listed, which also discuss interactions of this remedy with chemically defined drugs.

 

2.    Search for articles regarding a specific herb or food involved in chemically defined drug interaction, not knowing the preferred term (mostly English name) of the remedy:

You first have to search for this term in the index of investigated herbs and foods, because the main file is sorted by the preferred term of the remedy. In the index of investigated herbs and foods bold names represent preferred terms. Then you can access this remedy in the main file analogous to example 1.

 

3.    Search for articles regarding a specific chemically defined drug involved in an interaction:

First you search in the index of investigated chemically defined drugs for the therapeutic group of the drug and then the drug itself. There, you get the article identifications of the articles which investigated this drug in the context of interactions with a herb or food. Detailed information about these articles are available in the main file.

 

4.    Search for articles of a specific author:

The index of authors states next to the author’s name all article identifications of articles where the author was first or co-author, depending on whether the article identification is bold or not. Information about these articles and the full bibliographical reference can be found in the main file.