Featured Research

from universities, journals, and other organizations

Herbal and dietary supplements can adversely affect prescribed drugs, says extensive review

Date:
October 24, 2012
Source:
Wiley
Summary:
A number of herbs and dietary supplements (HDS) can cause potentially harmful drug interactions, particularly among people receiving medication for problems with their central nervous or cardiovascular systems. Researchers examined 54 review articles and 31 original studies. They found that the greatest problems were caused by interactions between prescribed drugs and HDS that included ingredients such as St John's Wort, magnesium, calcium, iron or ginkgo.

A number of herbs and dietary supplements (HDS) can cause potentially harmful drug interactions, particularly among people receiving medication for problems with their central nervous or cardiovascular systems.

Related Articles


Those are the key findings of an extensive research review published in the November issue of IJCP, the International Journal of Clinical Practice.

Researchers examined 54 review articles and 31 original studies. They found that the greatest problems were caused by interactions between prescribed drugs and HDS that included ingredients such as St John's Wort, magnesium, calcium, iron or ginkgo.

"Consumer use of HDS has risen dramatically over the past two decades" says co-author Dr Hsiang-Wen Lin from the College of Pharmacy, China Medical School, Taiwan.

"In the USA, for example, it is estimated that more than 50 per cent of patients with chronic diseases or cancer use them and that many patients take them at the same time as prescribed medication.

"Despite their widespread use, the potential risks associated with combining HDS with other medications, which include mild-to-severe heart problems, chest pain, abdominal pain and headache, are poorly understood."

Key findings of the review included:

  • The literature covered 213 HDS entities and 509 prescribed medications, with 882 HDS-drug interactions described in terms of their mechanisms and severity.
  • Warfarin, insulin, aspirin digoxin and ticlopidine had the greatest number of reported interactions with HDS.
  • More than 42 per cent of the drug interactions were caused by the HDS altering the pharmacokinetics of the prescribed drugs -- the process by which a drug is absorbed, distributed, metabolised and eliminated by the body.
  • Just over 26 per cent of the total were described as major interactions.
  • Among the 152 identified contraindications, the most frequent involved the gastrointestinal system (16.4%), neurological system (14.5%) and andrenal ⁄ genitourinary diseases (12.5%).
  • Flaxseed, echinacea and yohimbe had the largest number of documented contraindications.

"Our extensive review clearly shows that some HDS ingredients have potentially harmful drug interactions that are predominately moderate in their severity" says Dr Lin. "It also showed that herbal and botanical remedies were more likely to have documented drug interactions and contraindications than the other dietary supplements, such as vitamins, minerals and amino acids."

In an editorial on the review, Professor Edzard Ernst, Emeritus Professor, University of Exeter says that the authors provide an impressively complete overview of a fascinating and potentially important subject.

"Survey after survey shows that large proportions of the population are trying 'natural' remedies for illness-prevention, all sorts of ailments, diseases or for states of reduced well-being" he says. "Most experts therefore agree that the potential for such interactions is substantial.

"Despite this consensus and despite the considerable amount of documented harm generated by such interactions, our current knowledge is still woefully incomplete."

Professor Ernst believes that the number of interactions between HDS and prescribed drugs could be under-reported and just the tip of the iceberg.

He feels that the situation calls for rigorous research, increased awareness of possible HDS prescription interactions by physicians and patients and greater government control of this public health issue.

"Patients deserve reliable information, and it is our duty to provide it" he says. "We have to become vigilant and finally agree to monitor this sector adequately. Each individual doctor can contribute to this process by routinely including questions about alternative medicine use in their medical history taking."


Story Source:

The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length.


Journal References:

  1. H.-H. Tsai, H.-W. Lin, A. Simon Pickard, H.-Y. Tsai, G. B. Mahady. Evaluation of documented drug interactions and contraindications associated with herbs and dietary supplements: a systematic literature review. International Journal of Clinical Practice, 2012; 66 (11): 1056 DOI: 10.1111/j.1742-1241.2012.03008.x
  2. Edzard Ernst. Interactions between drugs and supplements: the tip of an iceberg? International Journal of Clinical Practice, 2012; 66 (11): 1019 DOI: 10.1111/ijcp.12007

Cite This Page:

Wiley. "Herbal and dietary supplements can adversely affect prescribed drugs, says extensive review." ScienceDaily. ScienceDaily, 24 October 2012. <www.sciencedaily.com/releases/2012/10/121024101754.htm>.
Wiley. (2012, October 24). Herbal and dietary supplements can adversely affect prescribed drugs, says extensive review. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2012/10/121024101754.htm
Wiley. "Herbal and dietary supplements can adversely affect prescribed drugs, says extensive review." ScienceDaily. www.sciencedaily.com/releases/2012/10/121024101754.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Experimental Ebola Vaccine Shows Promise In Human Trial

Experimental Ebola Vaccine Shows Promise In Human Trial

Newsy (Nov. 27, 2014) — A recent test of a prototype Ebola vaccine generated an immune response to the disease in subjects. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins