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 Millions through license revenues
27.04.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>