I think I need help with this one. Two days ago I took a 50mg dose of Stavelo, together with my normal meds of rasagiline, amantadine, and trihexyphenidy at 8-00am. I switched on at 8-30am. Everything normal, but I then stayed on and on, until 3-00pm, when I switched off. That is 6.5 hours from one 5omg tablet!! I normally only get 2 to 3 hours,
What caused it, well I remembered taking a glass of fruit juice, namely grapefruit. I was aware of the restrictions of drugs and grapefruit juice but nothing generally affects me. I duplicated the experiment yesterday and again got exactly the same result.
The only negative point is safety. There are about 50 drugs which interact with grapefruit, but are any PD drugs on the list? I did a quick search, and did not find any, but we need a very careful search. Apparently grapefruit juice and certain drugs both use ther same enzyme to break down.
If it is safe, this would be a huge step forward.
Ron

no clues here
http://www.parkinsonswellness.org/nutrition.html
someone likes orange juice, stomach acidity
http://www.centralohioparkinson.org/...e=doc&id=10098

Ron-
I did a little looking (but not in depth). It seems that there are two or three ways for grapefruit juice to affect the apple cart-
1) It can influence the actions of certain enzymes (e.g. cytochrome P450) and affect serum levels of medications that are broken down by those enzymes. Depending on the medication, those levels can increase or decrease.
2) It can increase bioavailability of drugs that are absorbed from the small intestine by increasing the permeability of that barrier. This is the one that intrigues me for obvious reasons.
3) There are hints of a similar effect at your old friend the BBB, too.

Bottom line is a bit of trial and error, but it looks darned promising. -Rick

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Coincidently, I started about a month ago to drink grapefruit juice after a break of almost 6 years. I had stopped when I was put on statins.

I have not noticed an effect that I can directly attribute to grapefruit. However, the last few weeks have been good for me. I had put this down to more exercise, both normal and forced.

Regarding the literature, see the blog of D. J. Kroll:

http://scienceblogs.com/terrasig/200...a_drug_boo.php

"Grapefruit juice as a 'drug booster': don't try this at home"

Linking this to another current thread there are comments on the impact of grapefruit juice on DXM.

John

Hi Rick,
If that is a short literature search, gosh!!
I would love to know if anyone else experiences the boost in on time. However, take it carefully, interactions with certain drugs are very bad. Certainly I tried it for 2 days and had no bad symptoms or side effects. I don't think big pharma will be too pleased, probably why it is not widely known.
There is a list of 50 drugs where grapefruit juice intereacts with them, but I have not managed to find it yet.
Thanks again for your mamouth list of refs.
Ron

Hi Johnt,
Thanks for your link, it gives one explanation as to the mechanism of this boost to drugs.

"). So, taking felodipine while drinking grapefruit juice was essentially the same as taking a higher dose of the drug because its elimination from the body was slowed. Today's WSJ article and blog post discuss the experimental and commercial approach to using CYP3A4 inhibitors as "dose boosters" to minimize the dose one needs to take of some very expensive drugs.

I did say big pharma would not be amused!!
Before we get into this, is there a clinical trial somewhere in ther literature?
If there is, it is quite likely that it has been suppressed for reasons given above.
Levodpa is a cheap drug, but with over 5 million sufferers worldwide, half of the market being lost would be horrendous for the suippliers. From our point of view, halving your sinemet would delay the onset of dyskinesia, or reduced dyskinesia in more advanced patients.
Ron

does grapefuit basically add more entacapone affect?
http://www.drugbank.ca/drugs/DB00323
click on enzymes at the top.

I checked a few drug interaction lists and PD drugs aren't mentioned in the ones I saw. So I tried grapefruit juice with my Sinemet and Mirapex today with no effect. I used Ruby Red grapefruit juice, 100% juice, no sugar added. I wonder if the type of grapefruit juice makes a difference or maybe it's the different meds we're taking. Or like everyone keeps saying, we're all different. Hope it keeps working for you, Ron.

Hi Wendy,
Sorry you got no effect, but it may be the type of juice used or when you take it. I did not use red grapefruit It was a carton from a local supermarket marked as 100% grapejuice from concentrate. I don't know the optimum time to take it but I took the juice about an hour after taking my meds. There was no warning on the carton about it's effect on drugs.
Ron

Ron,

The more I read about this the more it sounds like an episode of the (USA) TV program "House".

Scary to mess with our personal drug factory that is the human body.

I'm going to try some grapefruit juice, but VERY cautiously!

Mike