Grape fruit juice

[Sanay]

Hello everyone,

My husband started today with 100ml of grape fruit juice first thing in the morning and had his sinemet 10 min later.

It started to effect within 15min and lasted for only about an hour whereas it usually lasts for about 2 hrs.

I suppose the grape fruit juice is to increase the effect of sinemet rather than reducing it.

Any suggestions would be helpful.

Shall we stop it or continue for a week to see the actual result.

Also we began with 500mg of B1 today.

Could this be the reason ?

[johntPM]

It is rarely a good idea to make two changes to a regimen at the same time. How can you know which of the changes are doing good, which are making no difference, and which are doing harm? This is especially the case with grapefruit juice which magnifies the effect of levodopa but also the effect of many other drugs (e.g statins), possibly leading to overdose.

[Sanay in reply to johntPM]

Yes i agree that we shouldn't have started botg at the same time..

But then again as grape fruit is supposed to magnify levadopa then y the early wear off..

It should have some explanation

[johntPM in reply to Sanay]

Grapefruit juice contains, along with a number of other active compounds, an inhibitor of the enzyme CPY3A4. CYP3A4 plays a large part in the metabolism of many drugs, including levodopa. By inhibiting the CYP3A4, grapefruit juice allows more of the levodopa to be turned into dopamine. It is only at this stage that the levodopa in the dose that you have taken can have a therapeutic effect. What is unclear to me, a least, is what proportion of the magnification is used to make peak levels higher and what part goes into increasing the half-life. Increasing peak levels has limited use, because you can often take more levodopa. But, increasing the half-life could be very useful: it would mean much more stable levodopa levels, pulsatile changes in these are implicated in dyskinesia.

As mentioned in my previous reply grapefruit juice has many interactions with other drugs. These can be dangerous. So, before looking into grapefruit juice, I would suggest that you discuss with your doctor, other inhibitors:

carbidopa, AADC, levodopa

entacapone, COMT, levodopa

rasagiline, MAO-B, dopamine

[Sanay in reply to johntPM]

Oh k agree to some extent that increasing half life is definetly better than increasing peak effect..

My husband is just 36 years old and have no other health conditions besides PD so he is not on any drugs except sinemet so we thought to give it a try without worrying about other drug interactions..

Guess the idea is a bit more complex than we expected so need to do a more thorough research before diving into it..

Thanks so much for ur response..

[Despe in reply to Sanay]

So sorry your husband was diagnosed with PD at this young age.

Please read the link below. The author is a PwP who's done extensive research on Grapefruit Juice and its ability to inhibit CYP3A4. If you click on his avatar you will find a lot more information. Hope, this helps.

healthunlocked.com/parkinso...

[Lucyitswd]

They say grapefruit is not good for you to have if you have pw

[Despe in reply to Lucyitswd]

Says who, if I may ask.

[Lucyitswd in reply to Despe]

All Neurologists and Any dietitian who have any specific knowledge and you have proved it. So thank you x

[Despe in reply to Lucyitswd]

Not Dr. Mischley. Doctors/neurologists don't want you to know about GJ and its efficacy and bioavailability.

[chartist]

Dr. Costantini advised against taking citrus type juices at the same time as B-1. I think the reason was because it could affect absorption of the B-1 and could vary from person to person. He was more interested in seeing how just B-1 alone would affect the patient with as little interference as possible form other supplements or sources.

Art

[Sanay]

Agreed so just stopped it immediately..

Now no additions with B1