Navigation Links
More New Drugs a Bad Fit With Grapefruit, Study Finds
Date:11/26/2012

By Steven Reinberg
HealthDay Reporter

MONDAY, Nov. 26 (HealthDay News) -- Because of new chemical formulations, prescription drugs that interact badly with grapefruit have more than doubled in number since 2008, yet many doctors seem unaware of this, Canadian researchers report.

"The number of drugs on the market with the potential to produce serious adverse and in many cases life-threatening effects when combined with grapefruit has markedly increased over the past few years from 17 to 43 in four years," said lead researcher David Bailey, from the Lawson Health Research Institute in London, Ontario.

"There is much greater need for health care professionals to understand grapefruit/drug interactions and to apply this information to the safer use of these drugs in their clinical practice," Bailey said.

Even small amounts of grapefruit or grapefruit juice have the potential to cause sudden death, acute kidney failure, respiratory failure, gastrointestinal bleeding and other serious side effects when paired with these medications. Included are certain cholesterol-lowering medications, blood pressure drugs, cancer treatments and antibiotics such as erythromycin, the researchers said.

According to their review article, published Nov. 26 in the Canadian Medical Association Journal, more than 85 drugs may interact with grapefruit. Forty-three of these can have serious side effects, the researchers said.

Citrus fruits such as limes and Seville oranges, often used in marmalade, also contain the active ingredients -- called furanocoumarins -- that cause the dangerous interactions, the researchers said. The chemicals apparently inhibit an enzyme that normally deactivates about half the effects of medication.

All the drugs that interact with these chemicals are taken orally and don't metabolize well, meaning much of the drug passes through the body without entering the bloodstream. All are metabolized in the stomach in the same way, the researchers said.

A small amount of grapefruit, even ingested hours before taking the medications, can increase the amount of the drug metabolized, which is like taking many doses at once, the researchers said.

The toxic effect can build when the drug is taken repeatedly. For example, if the cholesterol-lowering drug Zocor is combined with a 7-ounce glass of grapefruit juice once a day for three days, the drug in the bloodstream will increase 330 percent, Bailey said.

According to the report, drugs that can interact with grapefruit include:

  • Certain cholesterol-lowering statin drugs, such as Zocor (simvastatin), Lipitor (atorvastatin) and Pravachol (pravastatin),
  • Some blood pressure-lowering drugs, such as nifedipine (Nifediac and Afeditab),
  • Organ transplant rejection drugs, such as cyclosporine (Sandimmune and Neoral),
  • Certain cardiovascular drugs, such as amiodarone (Cordarone and Nexterone), clopidogrel and apixaban.

Because people older than 45 are the major buyers of grapefruit and are more likely than younger individuals to take a variety of medications, they are most at risk. Also, because of their advanced age, they are most vulnerable to the harmful reactions of grapefruit-drug combinations, the researchers said.

Dr. Gregg Fonarow, a spokesman for the American Heart Association and a professor of cardiology at the University of California, Los Angeles, said little is known about how often these adverse effects occur in real world practice. Further studies are necessary, he added.

"Patients taking medications where there are potentially serious adverse interactions should, in general, be advised to avoid consumption of moderate or large quantities of grapefruit, or together with their physician consider potential alternative medications that are not metabolized by the liver enzyme inhibited by grapefruit," Fonarow said.

More information

For more information on drug interactions, visit the U.S. National Library of Medicine.

SOURCES: David Bailey, Ph.D., Lawson Health Research Institute, London, Ontario, Canada; Gregg Fonarow, M.D., spokesman, American Heart Association, professor of cardiology, University of California, Los Angeles; Nov. 26, 2012, Canadian Medical Association Journal


'/>"/>
Copyright©2012 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Continued Use of ADHD Drugs May Reduce Criminal Behavior, Study Says
2. UAlberta prostate cancer researcher and team developing homing beacon drugs to target cancer cells
3. Can breast cancer cells reaction to cancer drugs be predicted?
4. Quick, high-volume test offers fast track in search for Alzheimers drugs
5. Structure of enzyme unravelled providing basis for more accurate design of chemotherapeutic drugs
6. Injectable sponge delivers drugs, cells, and structure
7. Game changer for arthritis and anti-fibrosis drugs
8. First trial in humans of minicells: A completely new way of delivering anti-cancer drugs
9. Testing pain killers on humans could save money and speed the arrival of new drugs
10. Patients with aberrations in two genes respond better to drugs blocking a well-known cancer pathway
11. New Diabetes Drugs Have Different Advantages, Study Says
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
More New Drugs a Bad Fit With Grapefruit, Study Finds
(Date:5/28/2016)... ... May 28, 2016 , ... SuperCloset is proud to officially ... the day to day issues, struggles and obstacles veterans’ need to overcome in order ... Project provides active or retired military veteran(s) with a donated SuperCloset product based on ...
(Date:5/27/2016)... ... May 27, 2016 , ... More than a third of American adults ... that bariatric surgery has received increased attention in recent years, as an article ... comes to weight loss, most people are familiar with the basic requirements of maintaining ...
(Date:5/27/2016)... ... May 27, 2016 , ... With over 60 percent of acute stroke survivors ... sustainable product to aid in the rehabilitation process has steadily increased. Ekso Bionics had ... with hemiplegia due to stroke. , Ekso Bionics has now received clearance from the ...
(Date:5/27/2016)... NY (PRWEB) , ... May 27, 2016 , ... ... world, this installment is bolstered by inspiring human interest stories, courtesy of leaders ... developing trends and tech within the industry, from leading advocates and associations—namely Jones ...
(Date:5/26/2016)... ... 2016 , ... There are many ways to cook a hot dog, but ... Americans prefer their dogs straight off the grill. Of the 90 percent of Americans ... to cook a hot dog, far outpacing other cooking methods such as steaming (12 ...
Breaking Medicine News(10 mins):
(Date:5/27/2016)... Amarantus BioScience Holdings, Inc. (OTCQX: AMBS), ... Neurology and Orphan Diseases, today announced that President & CEO ... conferences: SeeThru Equity MicroCap Conference   ... City , NY When: Tuesday, May 31 st ... Where: Grand Hyatt Hotel, 109 East 42 nd ...
(Date:5/26/2016)... WASHINGTON , May 26, 2016 ... Microspheres, Associated With Both Cost Savings and ... BTG plc (LSE: BTG), an international specialist healthcare ... data at the 21st Annual Meeting of ISPOR ... that treatment of hepatocellular carcinoma (HCC) using yttrium-90 ...
(Date:5/25/2016)... , May 25, 2016 According ... by Type (3D, 2D, 4D), by Therapeutic Area (Oncology, ... End User (Medical Device Manufacturers, Hospitals/ Clinics) - Forecast ... global Medical Animation Market for the forecast period of ... USD 301.3 Million by 2021 from USD 117.3 Million ...
Breaking Medicine Technology: