Dangerous Drug interactions with grapefruit
http://www.ncbi.nlm.nih.gov/pubmed/17112309
Grapefruit juice and drug interactions. Exploring mechanisms of this interaction and potential toxicity for certain drugs.
Bressler R1.
Author information
Abstract
Concomitant administration of grapefruit juice can increase the plasma concentration of numerous drugs in humans and decrease the concentration of a few others. Such elevations of drug plasma concentrations have, on occasion, resulted in adverse clinical effects. Increased concentrations are primarily mediated by chemicals in grapefruit juice, which inhibit the CYP 3A4 drug-metabolism enzyme in the small intestines. This inhibition decreases the first-pass metabolism of drugs using the CYP 3A4 intestinal system and increases the bioavailability and maximal plasma drug concentrations (Cmax) of the CYP 3A4 substrates. The effect of grapefruit juice on drug metabolism is most pronounced in drugs with a high first-pass metabolism (eg, felodipine, amiodarone), in which it inhibits the first-pass metabolism of the CYP 3A4 substrates leading to an increase in Cmax and area under the concentration time curve (AUC). The use of grapefruit juice with a few specific drugs (eg, fexofenadine, digoxin) may lower plasma drug concentrations by inhibiting drug absorption catalyzed by the organic anion transporting polypeptide (OATP).
Cialis is putting warnings on prescriptions now saying don't mix with grapefruit
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What is exactly cyp
A simple Google search would have found you the answer, but here it is anyway, courtesy of Wikipedia:
Cytochrome P450 3A4 (abbreviated CYP3A4) is an important enzyme in the body, mainly found in the liver and in the intestine. It oxidizes small foreign organic molecules (xenobiotics), such as toxins or drugs, so that they can be removed from the body.
While many drugs are deactivated by CYP3A4, there are also some drugs which are activated by the enzyme. Some substances, such as grapefruit juice and some drugs, interfere with the action of CYP3A4. These substances will therefore either amplify or weaken the action of those drugs that are modified by CYP3A4.
CYP3A4 is a member of the cytochrome P450 family of oxidizing enzymes. Several other members of this family are also involved in drug metabolism, but CYP3A4 is the most common and the most versatile one.
Nice contribution to the forum thanks bro +1
..amazing what a simple Google search will pull up ;D
Thanks mate. I actually was asking myself the same question so the guy motivated me to find out.
There's a lot of prescription medication that has "do not consume grapefruit / grapefruit juice" within the small print that nobody ever reads. It's actually very well known in drug production.
Yeah I just learned about it recently so maybe this will help some guys that didn't know like myself, kind of interesting imo
Here's another list
http://pharmacistsletter.therapeuticresearch.com/pl/ArticleDD.aspx?nidch...
https://en.m.wikipedia.org/wiki/Grapefruit%E2%80%93drug_interactions
And a more detailed explanation so when in doubt just be careful, because all the interactions probably haven't been discovered yet... I originally posted this because I know alot of sources carry Viagra and alot of guys use it .
So...what would actually be useful here would be listing any AAS orals, ai's, SARM's etc. that grapefruit would have an impact on.
Statins (Cholesterol Lowering Drugs)
Antihistamines: Terfenadine
Calcium Channel Blockers (Blood Pressure Drugs):
Anti-convulsant: Tegretol (Carbamazepine)
Anxiolytics: Valium (Diazepam)
Anti-depressant: Sertraline Clomipramine
Cortico-steroids: Methylprednisolone
Oestrogens: Ethinyl estradiol
Anabolic Steroids: Dianabol
Impotence Drug: Viagra and cialis
Grapefruit juice-drug interactions.
Bailey DG, Malcolm J, Arnold O, Spence JD.
Department of Medicine, London Health Sciences Centre, Ontario, Canada.Br J Clin Pharmacol. 1998 Aug;46(2):101-10.
Alot of drug interactions are still being discovered, I guess originally it was tto test interactions with alcohol but the mixed drink had grapefruit in it so they inadvertently discovered that grapefruit interacts with alot of drugs... I have read that with some 17A orals it can increase bioavailability 500 percent but I don't know if that's bro science, I'll have to see if I can find a study to back it up... as you see above it can increase or decrease metabolism depending on the chemical
Is dbol the only oral AAS you have come across that it effects.
No I'm still finding more as you can see it can increase effectiveness of some and decrease others so you could easily throw off your estro or allow to much rebound
Tamoxifen (Nolvadex): Tamoxifen is metabolized by CYP2D6 into its active metabolite 4-hydroxytamoxifen. Grapefruit juice may potentially reduce the effectiveness of tamoxifen
exemestane, aromasin, and by extension all estrogen-like compounds and aromatase inhibitors which mimic estrogen in function will be increased in effect, causing increased estrogen retention and increased drug retention.[49]
keep digging. Getting some good info.
I'll simplify it so it's not a book to read haha and just throw the sources up top for verification.
Lol i thought was interesting myself... it might explain a few things for some guys still getting flare ups while taking nolva. I mean who would of thought to ask are you eating grapefruit? I'll try and put a complete list together and repost. Just wanted to get some intelligent discussion opened up, thanks for taking interest, wheels are turning.
Grapefruit can either inhibit a drugs action, and or induce a drugs action by means of CYP3A4/2D6 and through P-glycoprotein.
Cialis is a substrate of CYP3A4, therefore is susceptible to be inhibited by grapefruit, thus allowing the drug (cialis) to stay active in our body.
Grapefruit doesn't "neutralize" any drug. It either potentates or decreases the drugs activity.
Over 82 drugs interact with grapefruit 42 of which could be potentially fatal