"This study is an important step in understanding how N-acetylcysteine might work as a potentially new avenue for managing Parkinson's patients. The NAC appears to enable dopamine neurons to recover some of their function,"
Managing PD does not sound like disease modifying but if dopamine neurons can recover some of their function that does.
In the NAC group, significantly increased DAT binding was found in the caudate and putamen (mean increase from 3.4% to 8.3%) compared with controls (P < 0.05), along with significantly improved PD symptoms (P < 0.0001). The results suggest NAC may positively affect the dopaminergic system in patients with PD, with corresponding positive clinical effects.
I’ve taken. NAC since being diagnosed 6 years ago. I think my decline is quite slow but it is difficult to know if NAC has helped. I’ve also taken azilect since diagnosis and I am 58 so relatively young when diagnosed.I take 600mg a day.
Finally, this study showed that some people with PD had worsening of their Parkinsonian symptoms with high doses of NAC that resolved with discontinuation of therapy.
Several of the comments in the discussion section caused me to wonder if there is really any point taking oral NAC at doses of less than multiple grams.
There was a thread a while back about a dr who has PD. He is receiving NAC IV. Doesnt mean its the correct thing to do, but its interesting.
Interesting. Maybe instead of taking it on an ongoing basis, short duration intervals of high dose could be affective. Just a hypothesis. Im wary of high doses for long periods without a lot of evidence of safety.
I have no recollection of your ever agreeing with taking any supplements. Asking again, do you take any at all or are you against all supplementation? If you do take any supplements and if you have PD, what do you take? Im genuinely interested because if any can make it past your scrutiny than I want to look in to it as well. Are you suggesting IV NAC as a genuine alternative or an intentional dead end?
“taking NAC is considered one potential way to circumvent this problem. NAC increased glutathione levels and other antioxidants better than glutathione supplements when taken orally in a study of 20 people. But sublingual glutathione (which is not widely available) had stronger effects than either NAC or oral glutathione after 3 weeks [42].”
Liposomal glutathione is available by a few suppliers as is a nasal version. I have read NAC absorption best on empty stomach.
This is some info on NAC. There was a long list of potenial "serious adverse reactions" mostlyly with IV NAC, some with oral NAC. The most common were gastorintestinal. I did not list all the adverse.
Gastronintestinal: Orally, gastrointestinal complaints are the most common adverse effects reported with N-acetyl cysteine. These include heartburn (64608,64715,64717,64738,64739,102666), dyspepsia (1710,64715,64717,64724,64738), and epigastric pain (2260,10429,64715,64717). In one case report, esophagitis related to ulcerations occurred following intake of N-acetyl cysteine while in the supine position with inadequate water (102655). Other common side effects include loss of appetite (64715,64812), flatulence (2256,64510), diarrhea (64713,64715,97049), constipation (64715), dry mouth (64715,64724), nausea (7868,11430,64715,64724,64738,64812,97049), vomiting (64717,64724,64715,97049), gastric upset (64510,64545,97045,97049), and intolerance to taste and odor (64510,64545). N-acetyl cysteine's unpleasant odor makes it difficult for some patients to take orally. Using a straw to drink N-acetyl cysteine solutions can improve tolerability. Additionally, placement of a nasogastric or duodenal tube and administration of metoclopramide or ondansetron can be helpful for patients unable to tolerate oral N-acetyl cysteine (17).
Intravenously, N-acetyl cysteine may cause diarrhea (64712), dyspepsia, nausea, vomiting (64763), mild gastrointestinal upset (102657), and metallic taste (64763).
When inhaled, N-acetyl cysteine may cause epigastric pain and throat irritation (64703,64707,64674). IV NAC had BP problems.
Cardio vascular: Intravenously, N-acetyl cysteine has been reported to significantly increase systolic and diastolic blood pressure after exposure to nitroglycerin when compared with placebo (2280). Tachycardia, chest pain, angina, and transient sinus bradycardia have been rarely reported after administration of intravenous N-acetyl cysteine (2280,7872,64658).
N-acetyl cysteine (NAC) is a derivative of the amino acid L-cysteine. In the body, it is a source of sulfhydryl (-SH) groups, which allows it to act as a potent antioxidant. Also, N-acetyl cysteine increases glutathione levels in the body; glutathione deficiency is associated with a variety of pathological conditions (7868,64613,64681,64765,64770,64785).
Oral and intravenous N-acetyl cysteine, as prescription drug products, are effective for treating acetaminophen poisoning.
Atelectasis. When inhaled, N-acetyl cysteine is effective for treating atelectasis.
Bronchial diagnostic studies. When inhaled, N-acetyl cysteine is effective for bronchial diagnostic study preparation.
Tracheostomy care. When inhaled and used as adjunct therapy, N-acetyl cysteine is effective for preventing endotracheal crusting in patients with a tracheostomy.
POSSIBLY EFFECTIVE
Angina. Oral or intravenous N-acetyl cysteine may reduce nitroglycerin tolerance in patients with angina. However, some studies suggest that N-acetyl cysteine might increase the risk for severe headaches and hypotension when used with intravenous or transdermal nitroglycerin.
Autism spectrum disorder. Oral N-acetyl cysteine may improve irritability, but not other symptoms, associated with autism spectrum disorder.
Bronchitis. Via inhalation, N-acetyl cysteine is FDA-approved for managing acute episodes of bronchitis. Oral N-acetyl cysteine may help to reduce the occurrence of acute exacerbations of chronic bronchitis when used for 3-36 months.
Chronic obstructive pulmonary disease (COPD). Taking N-acetyl cysteine orally seems to decrease the exacerbation rate and improve symptoms in patients with moderate to severe COPD, particularly those who are not taking inhaled corticosteroids. Also, taking N-acetyl cysteine along with standard therapy appears to improve recovery in patients hospitalized due to an acute exacerbation.
Contrast induced nephropathy. Oral or intravenous administration of N-acetyl cysteine seems to prevent contrast induced nephropathy in patients with kidney dysfunction. However, it is not beneficial in those with normal kidney function or diabetes.
Hyperhomocysteinemia. Oral N-acetyl cysteine seems to reduce homocysteine levels.
Hyperlipidemia. Oral N-acetyl cysteine seems to reduce lipoprotein(a) levels.
Ifosfamide (Ifex) toxicity. Oral N-acetyl cysteine may be beneficial for reducing ifosfamide toxicity, although it does not appear to be as effective as mesna.
Influenza. Oral N-acetyl cysteine may reduce the risk for symptomatic influenza.
Kidney failure. Oral N-acetyl cysteine may reduce the risk for cardiovascular events in patients with kidney failure.
MI. Intravenous N-acetyl cysteine, along with standard therapy, seems to improve outcomes in patients with MI. Oral N-acetyl cysteine has not been evaluated for this use.
NOTE: FDA did attempt to pull NAC off market and make it prescription only see below statement:
N-acetyl cysteine is approved as a drug by the US Food and Drug Administration (FDA). Because it was approved as a drug before being marketed as a dietary supplement, N-acetyl cysteine is considered an unlawful ingredient in dietary supplements (104163). However, N-acetyl cysteine has been used in dietary supplements for decades. As of 2020, an increase in warnings from the FDA to companies using N-acetyl cysteine in their products has become a source of controversy for the US supplement industry.
Hinz protocol uses 4500 mg oral l-Cysteine per day. Doctor says it is more absorbable or more recognized by the body than NAC. I haven’t researched it but wanted to share this info that I’ve been given.
i've been taking NAC (along with 40+ other supplements). I'm very early stage PD. Today I had my worst symptoms (sustained and overt tremors in the face and mouth). So no evidence that ANY of my stack is helping in any way. Good luck to you.
Symptoms come and go. Just when I think I’ve gotten worse they go away are are replaced by something else. So, our N of 1 response has limitations. Which is why science and reproducible outcomes is the best evidence.
This is my doctor’s response after I sent him the link you posted. I’m just sending as a matter of interest about NAC vs l cysteine. He said
“I disagree with that. The neuroscience Center I am afiliated with studied this for many years. NAC is not natural for our bodies . L-Cysteine is a natural part of methylation pathway in human body. “
So much conflicting information it’s hard to know what to do. All the best
Very interesting! I had never considered replacing NAC with L-Cysteine until this. Thank you! Did they recommend a brand or source? Sounds like you have a good doctor, knowledgable and responsive. Is he/she a functional medicine doctor?
Nutritional Frontiers, Gateway discount nutrition, both in Pittsburgh Pennsylvania. Let me know if you need phone numbers. You can Google them. Also Medical Wellness in Jeanette PA 18008344325
Thanks so much. I have been looking for a source for a while. I took NAC for 6 months and it seemed to make a difference with a mild compulsive urge I developed recently.
He is a functional medicine doctor. He is guiding me with the Hinz protocol which I am trying. The supplements in the Hinz protocol use l cysteine. I will be speaking with him soon and will try to get more info. I know it is very confusing as one hears all the time about the benefits of NAC and rarely hear about l cysteine.
Here's the link to the latest Science of Parkinson's post on NAC which provides information about how NAC works and the scientific background of why it has been of interest in Parkinson's: scienceofparkinsons.com/201....
We would be keen to see a larger and longer clinical trial to evaluate whether NAC has any disease modifying effects as all the studies so far have been quite small and over a relatively short duration.
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