using grapefruit juice to increase oral AS absorption

We are talking about Grapefruit Juice Only. Not Grape Juice. Not Orange Juice. Only Only Only Grapefruit Juice

Can grapefruit juice influence ethinylestradiol bioavailability?
Weber A, Jager R, Borner A, Klinger G, Vollanth R, Matthey K, Balogh A.

Department of Clinical Pharmacology, Friedrich Schiller University of Jena, Germany.

The effects of grapefruit juice on the bioavailability of 17 alpha-ethinylestradiol (EE2) after a single oral administration of 50 micrograms EE2 have been investigated. The pharmacokinetics of EE2 were studied in an open, randomized, cross-over study in which 13 healthy volunteers were administered the drug with herbal tea or grapefruit juice (naringin, 887 mg/ml). In contrast to herbal tea, grapefruit juice increased the peak plasma concentration (Cmax) significantly to 137% (mean; range 64% to 214%, p = 0.0088) and increased the area under plasma concentration-time curve from 0 to 8 hours (AUC0-8) to 128% (mean; range 81% to 180%, p = 0.0186). This study shows that grapefruit juice increases the bioavailable amount of EE2. A possible explanation may be that grapefruit juice inhibits the metabolic degradation of EE2. Whether the increased bioavailability of EE2 following grapefruit juice administration is of clinical importance should be investigated in long-term studies.

Publication Types:
Clinical trial
Randomized controlled trial

PMID: 8631189 [PubMed - indexed for MEDLINE]

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[/b]side note: also be aware that this is a study a 17a hormone, but not a test on AS.[/b]

also, if you are taking 40mg dbol with grapefruit, im unsure if how much you should adjust the dose lower.

also read that over time your body keeps increasing its ability to absorb drugs over time,so after one week of Grapefruit juice with AS your body will be able to absorb more AS in week 2 than in week 1 when drinking Grapefruit juice concurrently.

Increasing effectiveness with grapefruit juice may increase toxicity. Get your liver supps in order.

Europe is the leader in doctors prescribing natural health remedies. The doctors there instruct patients to take GF juice with their medications to lower dosages and costs for patients. This applies to most meds taken orally.

Please read all of the studies I posted below. There some drug interactions to be aware of and also information for and against the use of grapefruit juice.

Currently I am searching for a link to a site that shows a bit more information on taking grapefruitjuice with medications besides the generic "take one glass of grapefruit juice".

Some hospitals have taken grapefruit juice off the list of possible drinks for patients to avoid problems with medication over dosing with medication prescribed by their doctors.

Lewd

In a randomized study of nine adults with cyclosporine-treated autoimmune diseases, grapefruit juice (5 ounces two times per day with cyclosporine, for ten days) caused a significant increase in cyclosporine blood levels compared with cyclosporine with water.17 The rise in cyclosporine blood levels was associated with abdominal pain, lightheadedness, nausea, and tremor in one patient. Using grapefruit juice to reduce the amount of cyclosporine needed has not been sufficiently studied and cannot therefore be counted on to produce a predictable change in cyclosporine requirements. The same effects might be seen from eating grapefruit as from drinking its juice

17. Ioannides-Demos LL, Christophidis N, Ryan P, et al. Dosing implication of a clinical interaction between grapefruit juice and cyclosporine and metabolite concentrations in patients with autoimmune diseases. J Rheumatol 1997;24:49–54.

BEWARE OF GRAPEFRUIT JUICE’S INTERACTION WITH CERTAIN DRUGS

It seems innocuous enough, but the lowly grapefruit can dangerously boost the action of certain drugs in the body. Healthcare managers may want to warn people of this, as it is easy to avoid.

Antihistamines Seldane and Hismanal and blood pressure medications Plendil, Renedil and Adalat have been known for a while to interact with grapefruit juice.

Now, a new study has found that the widely-used cholesterol-lowering agent lovastatin [Apo-lovastatin or Mevacor] can be added to the list of possible interactions.

Drinking moderate amounts of grapefruit juice can raise blood levels of lovastatin up to 15 times, causing rhabdomyolysis, a disintegration of muscle, and ultimately liver failure. The interaction was reported in the April 1998 issue of the Journal of Clinical Pharmacology and Therapeutics.

“This is very significant and very new. It is a huge interaction,’’ says Dr. Dave Bailey (PhD), a clinical pharmacologist at London Health Sciences Centre in London, Ont. and research scientist at the University of Western Ontario. Bailey was the first scientist in the world to discover that grapefruit juice can raise levels of drugs in the blood. His paper reporting an interaction between felodipine [Renedil, Plendil] and grapefruit juice was published in The Lancet in 1991.

Grapefruit juice interaction has gone “from an academic curiosity to a fundamental aspect of therapeutics,” he says, adding that the list of affected drugs will grow. With lovastatin, he said, it was “a real shocker. We did not predict it would be that significant a risk.’’

Lovastatin is taken by millions of North Americans; it was prescribed 949,000 times from May 1997 to April 1998 in Canada, according to health information company IMS Canada. The statins, says Bailey, are “good, safe drugs when taken properly.’’

Merck Frosst, the manufacturer of Mevacor, is aware of the dangers of grapefruit juice with Mevacor. According to spokesperson Denis Boucher, Merck has submitted a new product monograph (prescribing information) to Health Canada “which includes changes relating to grapefruit juice.’’

But Bailey says changes like that — which would warn doctors of the danger — take a long time. “It’ll take Health Canada two years to get the product monograph changed. It took them four years with felodipine.’’ (His paper was published in 1991 and the product monograph was changed in 1995.)

Other interactions with grapefruit juice:

Antihistamines terfenadine [Seldane] or astemizole [Hismanal].
Certain calcium channel blockers, such as Plendil, Renedil and Adalat.
Anti-rejection drug cyclosporine.
Cisapride [Prepulsid], a constipation drug.


http://www.assure.ca/library/periodic/chmaug98.htm

this study was conducted with males with HIV/AIDs since erectile dysfuntion is a common problem amongst some them.


http://www.aegis.com/files/catie/2002/tu125.pdf


Researchers in Koln, Germany, conducted a sudy using 24 healthy HIV negative male subjects whose average age was 29 years. The men received a glass of grapefruit juice on an empty stomach and then one hour later another glass of grapefruit juice with viagra 50mg. Blood samples were collected over the next 24 hours. a week later the experiment was repeated with water being substituted for grapefruit juice.

Results
Researchers found that the absorption of Viagra increased by 23% when taken with grapefruit juice instead of water. grapefruit juice also delayed the absorption of Viagra. This latter point is important because Viagra is supposed to be taken one hour before sex and taking the drug with grapefruit juice may result in disappointment for some users of viagra.

The grapefruit juice used in this study was white juice and supplied by Dohler-euro Citrus NBI,GMBH. Other brands,types, and doses of grapefruit juice may have different effect. The researchers suggest the combination of Viagra and grapefruit juice be avoided.

Men who use protease inhibitors are usually prescribed less than normal doses of Viagra because protease inhibitors can raise levels of Viagra several times greater than normal. So men who use protease inhibitors and Viagra should also avoid taking grapefruit juice with Viagra.

How Grapefruit Juice Makes Some Pills More Powerful
By ABIGAIL ZUGER

or four years, the patient was one of Dr. Paul Pizarik's bigger problems: a 63-year-old Arizona man with heart, lung and kidney disease, and blood pressure that stayed dangerously high despite combinations of a half-dozen different advanced medications.

And then suddenly, to Pizarik's great surprise, the man's pressure dropped into perfect control. It had been magically reduced by nothing more complicated than a six-ounce glass of grapefruit juice that the patient had decided to add to his morning pills.

A few weeks later, his pressure plunged so low that his medication had to be changed all over again.

Researchers have known since 1989 that when some of the common blood-pressure pills called calcium-channel blockers were washed down with grapefruit juice, far more of the drugs reached the blood than when they were taken with a swallow of water instead.

But it is a piece of information that has passed many doctors and patients by, even though the interaction has now been reproduced for other drugs. The effect may be so striking that some scientists are now calling for warning labels about the effects of grapefruit juice on pill bottles to prevent accidental drug overdoses. Others have hastened to patent the chemicals involved and are planning to incorporate them into new combination pills.

"We are harnessing the power of the grapefruit," said Dr. Paul Watkins, a professor of medicine at the University of Michigan in Ann Arbor, whose research recently clarified why grapefruit alone among citrus fruits appears to make some pills more powerful.

The handful of drugs now known to be involved include some common and potent ones, among them Plendil (felodipine) for high blood pressure and heart disease, Seldane (terfenadine) for allergies, Sandimmune (cyclosporine) to prevent rejection of transplanted organs, and Invirase (saquinavir) for treating AIDS.

What these diverse substances have in common is their fate after they pass through the stomach. Unlike other drugs that are absorbed directly from the intestine into the bloodstream, these are first extensively broken down by an enzyme in the wall of the small intestine.

In research published in The Journal of Clinical Investigation in May, Watkins and his colleagues showed that grapefruit juice appeared to remove large amounts of that enzyme from the intestinal wall.

The result is that less of the drug is broken down, more remains in the intestine and more is then absorbed into the bloodstream over a longer period, just as if the patient had actually swallowed a higher drug dose.

The specific causes appear to be chemicals in the juice called furanocoumarins or psoralens that function like "little suicide bombers," attaching to the enzyme and damaging it so badly that the entire complex disappears from the cell.

But the amount of the enzyme in the intestinal wall varies greatly among people, Watkins said, which explains why the grapefruit juice effect may be serious for some people and unimportant for others.

It probably makes very little difference if people with relatively low levels of the intestinal enzyme take their medicine with grapefruit juice or with water. But for others with a great deal of the enzyme, an unaccustomed glass of juice in the morning may send enzyme levels plummeting and drug levels soaring as much as ninefold.

Dr. J. David Spence at the Roberts Research Institute in London, Ontario, thinks this is what may have happened to a Michigan man who died in 1993 with toxic blood levels of Seldane after drinking two glasses of grapefruit juice. "The problem is that juice is taken intermittently," he said. "And grocers don't take a drug history when they sell it."

Seldane blood levels are increased not only by grapefruit juice but also by many common prescription drugs, and serious heart problems may result. Although the drug is under new scrutiny by the Food and Drug Administration for its toxicity, it remains available by prescription in this country and is sold over the counter in Canada.

In new prescribing information supplied to doctors only last month, Seldane's manufacturer, Hoechst-Marion-Roussel, added grapefruit juice to the list of substances that should not be taken with it.

Although information about grapefruit juice accompanies other affected drugs, it is printed in the tiny type reserved for doctors and pharmacists and seldom makes it out onto the patient's pill bottle. Many other drugs have never been specifically tested for grapefruit juice interactions.

The effect of a glass of grapefruit juice on drug levels lasts a day or more, and it increases over time, Spence cautioned. He favors a practice now routine in parts of Australia of affixing specific grapefruit juice warnings to pill bottles if an interaction is known or might be expected.


Other experts feel that chances of drug overdoses from a breakfast containing grapefruit are too small to warrant major public concern.

"These are generally safe drugs," Watkins said. "I just tell patients, if you're used to taking your medicines with juice, keep doing it. If you're not, don't start."

In fact, the danger of grapefruit juice impresses many scientists less than does its ability to augment drug effects cheaply and palatably without the need for larger doses.

Dr. Leslie Benet, chairman of the department of biopharmaceuticals at the University of California at San Francisco, has founded a corporation called Avmax to evaluate and market substances like those in grapefruit juice that inhibit intestinal enzymes, making drugs more available to the body with less person-to-person variability.

His company has licensed one of the patented chemicals responsible for the effect in grapefruit, and is beginning studies combining it with several prescription drugs.

Other doctors just direct patients to the supermarket. Like many doctors who treat AIDS, Dr. Nereida Ferran, an internist at Beth Israel Hospital in New York, routinely advises her patients taking Invirase for HIV infection to take it with grapefruit juice.

"The blood levels of the drug increase at least twofold," she said. "Many of my patients are doing very, very well on what is supposed to be one of the weaker HIV drugs."

And Pizarik remains aware of grapefruit's double-edged potential. Over time, his patient's initially elevated blood pressure dropped so low with grapefruit juice that the man almost went into shock.

"He became pretty pale and pasty-looking," said Pizarik, who has not given grapefruit juice to any other patients. "I don't know that I'd recommend it again until more studies are done."


http://www.geocities.com/CollegePark...grapefruit.htm

http://www.holistic-online.com/Herba...tions-home.htm

An excellent site which discusses the cytochrome P-450 3A4 isozyme at some length.

you should understand the P450 pathway if you are taking bromocriptine and other medications.

the conclusion of the article is something I saw a few times on other sites in regards to grapefruit juice usage:

If you are not currently taking your medications with grapefruit juice regularly, don’t start. If you are already taking your medications with grapefruit juice regularly, don’t stop. The exception to this guideline is for terfenadine (Seldane) and astemizole (Hismanal). Enough evidence exists of the danger of taking terfenadine with grapefruit juice that you should stop taking this with grapefruit juice immediately

With further research, it should be possible to eventually harness this drug enhancing effect of grapefruit juice to our advantage. However, at the present time, it would be more prudent to avoid drinking grapefruit juice when taking any medications that utilize cytochrome P450 3A4 isoenzymes for any of the steps in their respective metabolic pathways

Lewd

Very nice bro...Thanks for the time you took to educate us.:clapping:

thanks bro. some of the posts I made in this thread seem to contradict each other, but I want to give you the big picture. The closest study I saw on grapefuit juice and steroids was the first one using a female hormone. I will keep looking.

one glass of GF juice may effect some people and it may not effect others. results can be positive or negative. using P450 inhibitors works similar to GF juice but I am in no way suggesting you use inhibitors to increase absorption of AS. just be aware of it if you are using them. The thread in EDUCATIONAL THREADS named "Grapefruit juice and cytochrome P450 pathway" has a list of popular ones.

Just doing the research is a learning experience. A lot of drugs have contraindictions/drug interactions and everyone should be aware of that. It is easy to look up. but not spoken about much.

Quote:

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Originally posted by MindBomb
Very nice bro...Thanks for the time you took to educate us.:clapping:

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This will seem like a dumb question but, does this mean orals should be taken on an empty stomach with grapefruit juice? Or, like vitamins, should orals be taken with foods.
Will taking orals with food diminish the effects of the grapefruit juice?

Also, are there any resources or research of effect with various AS usages?

excellent thread.

BUMP

many hospitals have taken GF juice off their list of menut items for their patients to avoid drug overdose/toxicity issues. I can't suggest the use of GF juice for increasing the absorption of anydrug since it is unpredictable on how it will positively or negatively help each individual.

there are many inducers/inhibitors of the P450 pathway and I suggest you read that post also it will explain why you should avoid alcohol and other drugs for similar reasons when taking a number of medications(substrates).

Quote:

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Originally posted by lwb357
This will seem like a dumb question but, does this mean orals should be taken on an empty stomach with grapefruit juice? Or, like vitamins, should orals be taken with foods.
Will taking orals with food diminish the effects of the grapefruit juice?

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Maybe it is very effective with oral steroids. Maybe it isnt. I drink it with every Dbol I pop. BUMP.

wow that waas very educational. Thanks man

GF juice gives nolvaxed and clomid a great boost.
When using nolva with GF juice 10mg/ED is enough.
Others take 20mg`s of nolva without GF juice and still gets gyno.
I have used for 3 years GF juice and I have nothing but good results!!!

Nice post Bro - packed with info - bump to the top

Nice post. I just read something similar i believe on another board. The Grapefruit juice kills a particular enzyme in the stomach that decreases the potency of oral administration. This is good information. bump'n

what a great thread...i hate the stuff...but if its going to do that...i can learn to get along with it...what about injectables like prop...some results...i like what buddy said about the nolv..that is great info...thanks guys

Hell I'm definately willing to give it a try with the nolva and clomid. SAY NO
TO GYNO!!!

The boost with tamoxifene citrate (nolva) and clomifene citrate (clomid) comes cos they have that citrate bind and the citrate ascorbition is raised with use of GF juice.
It does not work with injektables.

possibly dumb question .. but I was wondering since I didnt see any mention of whether pink grapefruit or the yellow one is better or worse.

Very nice.