Doesn’t the Half-Life of C/L apply only t... - Cure Parkinson's

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Doesn’t the Half-Life of C/L apply only to, while in the bloodstream and once Levodopa crosses the BBB it is stored until used?

Gcf51 profile image
34 Replies

I posed a question in a comment and have not received an answer.

I am thinking that once L-dopa crosses the BBB it is stored until used (maybe as dopamine). And, Half-Life is how long it stays in your Blood Stream.

The plasma half-life of levodopa is about 50 minutes, without carbidopa. When carbidopa and levodopa are administered together, the half-life of levodopa is increased to about 1.5 hours. dailymed.nlm.nih.gov/dailym...

Note: because I changed the title, I reposted. My experience is; a link to a changed title will take you to page not found,

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34 Replies
park_bear profile image
park_bear

This is a good topic. Personally I have found that the effects of levodopa medication last a lot longer than the duration in the plasma.

Gcf51 profile image
Gcf51 in reply topark_bear

Probability the reason someone can take B6 within hours of taking C/L and not have problems.

WinnieThePoo profile image
WinnieThePoo

No. Normally levadopa is decarboxylated in the brain and the body. Peripheral levadopa conversion to dopamine is at best wasteful, at worst toxic. Levadopa has a half life of 1-3 hours. If it is combined with a DDCI like Carbidopa, it is inhibited from conversion to dopamine in its presence. Carbidopa is incapable of crossing the BBB and so allows more levadopa to cross into the brain, where it is converted at the same rate. But dopamine is also incapable of crossing the BBB - it's a 2 way thing, so the dopamine made in the brain stays there until used. That is why the effects of taking oral L/C last longer than levadopas half life.

Boscoejean profile image
Boscoejean in reply toWinnieThePoo

I guess what I find puzzling is that when my husband takes the compounded carbidopa with mucuna one time in the morning he seems to have benefits pretty much throughout the day and does not have to experience symptoms that are so often mentioned that are associated with having the standard carbidopa/levodopa medication wear off- maybe we are just lucky in this respect and not sure how long this will be helpful but the naturopath we saw mentioned that one of her patients was able to maintain on this combination for over 8 years and then eventually started using the standard medication

Gcf51 profile image
Gcf51 in reply toBoscoejean

Are you saying, he doesn't take mucuna or C/L for the rest of the day.

Boscoejean profile image
Boscoejean in reply toGcf51

yes

Gcf51 profile image
Gcf51 in reply toBoscoejean

How much C/L did he take before he started the carbidopa/mucuna

Boscoejean profile image
Boscoejean in reply toGcf51

he never took C/L. The neurologist wanted him to start it right away but he held off and did not even start the other until 2 years after diagnosis. It is possible he could have been diagnosed earlier however when he saw the neurologist in 2017 he was not willing to say if he had essential tremor or Parkinson's. He did not return to the neurologist and the neurologist retired then covid happened then we decided we wanted to schedule an appointment at OHSU because I thought maybe they would have the latest in what could help. It took 6 months to get in to the neurologist there and the appointment was a complete disappointment. He saw the neurologist there in September 2021 with a return visit January, 2022. We were not excited about going back to this neurologist but he is no longer there anyway. In the meantime I found out about a naturopath who practices at OHSU and she is also a researcher. She is not a neurologist but she was incredibly thorough and was very helpful. She has been working with patients with Parkinson's for several years so she has a lot of knowledge about research in the field.

Gcf51 profile image
Gcf51 in reply toBoscoejean

"did not even start the other" other as in carbidopa/mucuna

JayPwP profile image
JayPwP in reply toBoscoejean

Does this naturopath take online patients?

Boscoejean profile image
Boscoejean in reply toJayPwP

I do not know if the naturopath that we saw at OHSU does remote visits because we went there in person.

JayPwP profile image
JayPwP in reply toBoscoejean

Thanks. Please would you share her email address if any. I will contact her directly.Please PM me separately.

Smittybear7 profile image
Smittybear7 in reply toBoscoejean

where is OHSU?

Boscoejean profile image
Boscoejean in reply toSmittybear7

Oregon Health Sciences University, Portland, Oregon

Smittybear7 profile image
Smittybear7 in reply toBoscoejean

thank you

CuriousMe12 profile image
CuriousMe12 in reply toBoscoejean

Where do you source your mucuna and carbidopa from ?

Boscoejean profile image
Boscoejean in reply toCuriousMe12

our naturopath wrote a prescription for the carbidopa and we get it from a local compounding pharmacy - I know the pure mucuna powder is considered the best but so far we have just used the capsules and they are not a real high percent but we use the ones that have met purity guidelines

CuriousMe12 profile image
CuriousMe12 in reply toBoscoejean

Thanks. Not sure what route I'd take in the UK.

JayPwP profile image
JayPwP in reply toBoscoejean

I think it would be good if you make a detailed post on your husband's protocol... What, when, how and why? Please include Diet, exercise, medications, supplements, alternative therapies along with measurements and timings...

Apologies if done already...

Meg024 profile image
Meg024 in reply toBoscoejean

What dosage of Macuna (and what brand?) and carbidopa does your husband take?

Boscoejean profile image
Boscoejean in reply toMeg024

Carbidopa is 20 mg and Now and Doublewood capsules are 15%

Meg024 profile image
Meg024 in reply toBoscoejean

Thank you, can you share a link to the source of the carbidopa, please?

Gcf51 profile image
Gcf51 in reply toMeg024

I am not sure what's available in South Africa. She says she gets the carbidopa... from a local compounding pharmacy. Macuna, capsules 15% brands Now and Doublewood, should be available at a multitude of places. either Now, Doublewood or Amazon.

Meg024 profile image
Meg024 in reply toGcf51

Thank you

Boscoejean profile image
Boscoejean in reply toMeg024

The compounded carbidopa was prescribed by a naturopathic doctor and made by a compounding pharmacy.

Meg024 profile image
Meg024 in reply toBoscoejean

Thanks

Ghmac profile image
Ghmac in reply toBoscoejean

Boscoejean - can you tell me what your think these symptoms are? does not have to experience symptoms that are so often mentioned that are associated with having the standard carbidopa/levodopa medication wear off- My husband has just started taking C/L due to a reaction to covid and I am not sure about what these symptoms might be.

Thank you

Boscoejean profile image
Boscoejean in reply toGhmac

he does not have dyskinesia, dystonia, excessive slowness, and major increase in tremor that some individuals who take sinemet have when it wears off- there is generally no sharp drop in the benefits of the combination he takes

Ghmac profile image
Ghmac in reply toBoscoejean

Thank you

park_bear profile image
park_bear in reply toWinnieThePoo

Has any data been published on the duration of levodopa derived dopamine in the brain?

WinnieThePoo profile image
WinnieThePoo in reply topark_bear

I don't think there is any distinction between ldopa derived dopamine and "natural" dopamine. Dopamine systems are complicated, and there is much recycling.

Gcf51 profile image
Gcf51 in reply toWinnieThePoo

There probably isn't anyway to tell the difference, except maybe if the levodopa was a radioisotope.

Gcf51 profile image
Gcf51 in reply toWinnieThePoo

"dopamine made in the brain stays there until used" implies storage. That is if levodopa is converted to dopamine in the brain.

Added Note: "Thus, l-dopa is coadministered with drugs that block peripheral metabolism, including the AADC inhibitor carbidopa. Even with these drugs, up to 56% of l-dopa fails to reach the brain." science.org/doi/10.1126/sci...

JMDean profile image
JMDean in reply toWinnieThePoo

This is the correct answer :-)

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