Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Grapefruit juice and medication can be a deadly mix

18.01.2005


Grapefruit juice can be deadly for people on certain medications, nurse researchers remind doctors, nurses, and everyone who takes medicine and enjoys grapefruit juice, in a paper in the American Journal of Nursing, a journal of the American Nurses Association.



Amy Karch, R.N., M.S., of the School of Nursing at the University of Rochester Medical Center reported on a man from a northern climate who moved to Florida for the winter – one of tens of thousands of "snowbirds" who head south each winter – and began drinking two to three glasses of grapefruit juice each day. Two months later the man died, the victim of a deadly interaction between grapefruit juice and his cholesterol-lowering medication.

Karch’s paper, "The Grapefruit Challenge: The juice inhibits a crucial enzyme, with possibly fatal consequences," appears in the December 2004 issue of the journal.


Interactions between grapefruit juice and medications have long been recognized. Last year, the Medical Letter on Drugs and Therapeutics devoted an entire issue to grapefruit juice and the dangerous drug interactions that can result. The U.S. Food & Drug Administration requires all prospective new drugs to be tested for interactions with grapefruit juice. And a warning about grapefruit juice is included in the "food-drug interactions" that come with dozens of medications. Nevertheless, Karch says many health-care professionals and patients don’t know about the risk.

"The potential of drug interactions with grapefruit juice has been out there a long time, but most people just aren’t aware of it," says Karch, a clinical associate professor of nursing. "There is so much information bombarding people all the time, that a lot of people may have heard this but forgotten it. But the problems can be life-threatening."

The patient profiled in Karch’s article had high cholesterol and other risk factors for cardiac disease. The doctor put the patient on atorvastatin (Lipitor), and the patient began dieting and exercising. Two months after the patient went to Florida for the winter, he suddenly had muscle pain, fatigue and fever, and went to the emergency room. The patient ended up going into kidney failure and ultimately died.

The only major change in the person’s lifestyle had been that, upon arriving in Florida, he began picking grapefruit off a tree on the patio and drinking two or three glasses of fresh grapefruit juice every day.

Karch, an expert on drug interactions, explains that grapefruit juice is one of the foods most likely to cause problems with drugs, because it is metabolized by the same enzyme in the liver that breaks down many drugs. The cytochrome P-450 3A4 enzyme breaks down grapefruit juice into useful components for body, just like it breaks down dozens of medications. Karch says when the system is overloaded, the grapefruit juice can "swamp" the system, keeping the liver busy and blocking it from breaking down drugs and other substances.

Drugs that use the same pathway and interact with grapefruit juice target some of the most common health problems doctors see today. The list consists of more than 50 medications, including some drugs used to treat high cholesterol, depression, high blood pressure, cancer, depression, pain, impotence, and allergies.

Karch notes that interactions with grapefruit juice are well known and documented among drug researchers, and that an appropriate warning label is included with each prescription. Nevertheless, she says that many patients, nurses and doctors aren’t aware of the interactions or the potential serious consequences, and that many people fail to read the warning labels about drug-food interactions.

The consequences of an interaction depend on the drug involved. A woman on birth-control pills who drinks a lot of grapefruit juice might find herself pregnant because the juice blocks the action of the medication. A person on an anti-depressant might have too much or too little energy, depending on the specific medication. Someone on antibiotics might end up with diarrhea or could be ill longer than usual because the drug won’t work as well as it should. A heart patient might not get the lowered blood pressure that a medication should deliver, or the heart’s rhythms might become irregular if an anti-arrhythmia drug can’t do its job.

The most severe effects are likely with some cholesterol-lowering medications, Karch says. While the liver devotes its resources to grapefruit juice, the medication can build up to dangerous levels, causing a breakdown of the body’s muscles and even kidney failure. This is what happened to the patient discussed in the article.

To prevent such problems, Karch repeats what doctors and nurses tell their patients every day: Read a medication’s warning label carefully. If an interaction with grapefruit juice is possible, the patient should stop drinking the juice until speaking with his or her doctor. In some cases it might be possible to switch a patient to a different drug without the risk; in other cases the patient might simply have to give up grapefruit juice.

She says that more people than usual are vulnerable at this time of year, because losing weight is among the most popular New Year resolutions, and some diets are built around drinking lots of grapefruit juice.

Karch’s paper is the latest in a column the journal devotes to "practice errors," where nurses report unusual clinical problems and Karch looks into how widespread the problem might be. Last year she also reported that nurses had found that some types of skin patches could catch on fire when patients receive magnetic resonance imaging (MRI) scans.

Tom Rickey | EurekAlert!
Further information:
http://www.urmc.rochester.edu

More articles from Health and Medicine:

nachricht Laser activated gold pyramids could deliver drugs, DNA into cells without harm
24.03.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences

nachricht What does congenital Zika syndrome look like?
24.03.2017 | University of California - San Diego

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>