N-Acetyl-L-Cysteine boosts dopamine

N-Acetyl L-Cysteine (NAC)

David Tomen
Author:
David Tomen
Jill Corleone, RD
Fact Checked:
Jill Corleone, RD
14 minute read
N-Acetyl L-Cysteine (NAC) is a powerful anti-oxidant, can boost mood, lower anxiety, improve memory, and reduce compulsive behavior

Key Takeaways

  1. N-Acetyl L-Cysteine (NAC) is a powerful antioxidant that restores glutathione levels in the body and brain, helping maintain oxidative balance in cells.

  2. NAC has neuroprotective properties, reducing inflammation, oxidative damage, and modulating glutamate levels and dopamine release, positively impacting cognition, memory, and mood.

  3. NAC shows potential in treating serious cognitive disorders like schizophrenia, bipolar disorder, severe depression, and anxiety by boosting glutathione and dopamine levels in the brain.

  4. NAC can reduce oxidative stress, eliminate free radicals, rejuvenate dopamine receptors, and enhance cognitive function when taken as a supplement.

  5. N-Acetyl L-Cysteine (NAC) dosage recommendation is 500 mg, 3-times per day

N-Acetyl L-Cysteine (NAC or N-acetylcysteine) is the N-acetyl derivative of the naturally occurring amino acid L-cysteine. And works primarily by helping restore the body’s natural antioxidant glutathione (γ-glutamylcysteinylglycine; GSH).

As the most abundant antioxidant in your body, GSH is responsible for maintaining oxidative balance in each of your cells.

I have been using 500 mg NAC 3-times per day and every day for the last decade and it is one of my favorite supplements.

Taking glutathione as a nootropic supplement does not adequately restore GSH levels in your brain because it can’t cross the blood-brain barrier. This vastly underrated nootropic, NAC easily penetrates the blood-brain barrier and raises glutathione levels in your brain.[i]

NAC has been used to treat acetaminophen poisoning for decades.[ii] Every year there are 56,000 ER visits from Tylenol overdose, resulting in at least 100 deaths. [iii] NAC provides the glutathione your liver needs to fight off the metabolite NAPQI in Tylenol that does severe liver damage.

Studies show that as a nootropic, NAC helps prevent glutamate toxicity, boosts dopamine, and reduces inflammation, oxidative and free radical damage.

Where to buy: one of the only vendors still selling NAC and I highly recommend them: Life Extension – NAC

N-Acetyl L-Cysteine helps:

  • Neuroprotection. NAC as a precursor of glutathione, is a potent antioxidant, anti-inflammatory and free radical scavenger.[iv] Your brain is especially vulnerable to inflammation, free radical and oxidative damage. Affecting cognition, long-term potentiation, memory and mood.
  • Neurotransmitters. NAC modulates glutamate levels and dopamine release in the brain. Excess glutamate in your brain is toxic to brain cells affecting neuron health, cognition, memory and mood. And NAC protects dopamine receptors. Influencing dopamine levels and function in your brain. Even protecting dopaminergic nerve terminals from chronic methamphetamine use.[v]
  • Anxiety and depression. NAC reduces irritability, anxiety and depression. NAC increases your body’s antioxidant capacity, and balances excitatory and inhibitory neurotransmitters in your brain. Resulting in less anxiety and depression.

N-Acetyl L-Cysteine (NAC)

N-Acetyl L-Cysteine (NAC) is the N-acetyl form of the naturally occurring amino acid L-Cysteine.

N-Acetyl L-Cysteine (NAC) chemical structure
N-Acetyl L-Cysteine (NAC)

L-Cysteine is naturally produced in your body using the amino acid methionine. You can also get L-Cysteine from eating ricotta and cottage cheese, yogurt, pork, chicken, turkey, duck, wheat germ, granola and oat flakes.

But acute stress, illness, or a poor diet can deplete L-Cysteine levels in your body and brain. The quickest and most efficient way to boost levels of L-Cysteine is to supplement with N-Acetyl L-Cysteine (NAC).

NAC regulates the amount of glutamate in your brain. Glutamate is a neurotransmitter that is responsible for sending signals between neurons in the brain. This plays an important role in learning and forming memories.

But too much glutamate can be toxic to brain cells. NAC regulates the amount of glutamate and keeps it at safe, healthy levels.

NAC influences the amount of dopamine available in your brain. It works to keep dopamine receptors healthy and able to transmit and receive dopamine. These neurotransmitters are crucial for cognitive energy and drive, motor control, feelings of pleasure, and focus.

NAC is a precursor to the powerful anti-oxidant glutathione (GSH). GSH is a potent anti-inflammatory, anti-oxidant and free radical scavenger.

Your brain is especially vulnerable to inflammation, free radical and oxidative damage. If left unchecked, inflammation, oxidation and free radicals can negatively affect cognition, long-term potentiation, memory and mood.

As a nootropic, NAC can boost glutathione and dopamine levels in your brain. NAC is also used by medical professionals to treat serious cognitive disorders like schizophrenia, bipolar disorder, severe depression and anxiety.

N-Acetyl L-Cysteine boosts-brain derived neurotrophic factor (BDNF)

How does N-Acetyl L-Cysteine work in the Brain?

N-Acetyl L-Cysteine boosts brain health and function in several ways. But two in particular stand out.

  1. N-Acetyl L-Cysteine reduces oxidative stress. Oxidative stress is caused by free radical damage in brain immune cells. Leading to neurodegeneration and reducing brain health which can lead to Alzheimer’s, Parkinson’s and other age-related neuronal disorders. Proteins and DNA are injured, inflammation, tissue damage and cellular apoptosis (cell death) are the result.

And neurohackers are not immune to oxidative stress no matter what your age. Keep this in mind the next time you reach for a Diet Coke. Consumption of the artificial sweetener aspartame induces cortical inflammation and oxidative stress. And negatively affecting brain health.

Researchers did a study with 30 adult male Wistar rats randomly divided into 3 groups. The control group received distilled water. The second group was given aspartame. And the third group was given aspartame and NAC. Oral administration was done in the morning daily for 90 days.

The study found that NAC boosted Brain-Derived Neurotrophic Factor (BDNF) levels, blocked the COX-2 and PGE2 inflammatory enzymes, and reduced the expression of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) inflammatory cytokines in the rat cerebral cortex. They also found that NAC replenished glutathione levels.

The researchers concluded that NAC prevented neurotoxicity and improved neurological function, suppressed brain inflammation, and oxidative stress response.[vi]

  1. NAC relieves depression. Major depressive disorder is one of the most common psychiatric disorders. It’s a burden on the individual, family and the community. And the pharmaceutical companies are making literally billions on selling various anti-depressants. Not treating the cause, producing a host of side effects, and in most cases just ‘dumbing down’ the symptoms.

But the pipeline for new anti-depressant drug discovery is at a near stand-still for treating problems like schizophrenia, bipolar disorder, depression and common forms of autism.

The good news is that neuroscience continues to work on the problem. And have shown that many of these disorders share immune health issues such as inflammation and oxidative stress as part of their disease physiology.

Neuroscientists also discovered that associated pathways causing these diseases include a reduction in proteins that stimulate neuron growth (neurotrophins), increased apoptosis (cell death), and reduced energy generation in mitochondria.

It turns out that N-Acetyl Cysteine seems to have multiple effects on all these pathways. NAC reduces the core symptoms of schizophrenia, reduces depression, and reduces cravings for a number of addictions including cocaine, cannabis and tobacco.[vii]

How things go bad

As we get older or suffer from chronic illness, our brain and body chemistry and energy metabolism changes.N-Acetyl L-Cysteine relieves depression

↑ Oxidative stress in brain cells increase

↓ Free radicals damage neurons

↓ Dopamine receptors stop working

↑ Glutamate toxicity causes cell damage and apoptosis

↓ Brain-Derived Neurotrophic Factor (BDNF) declines

↓ Mitochondria energy declines

All of these changes are often attributed to chronic illness, lifestyle choices, and aging.

Unchecked, they could lead to neurodegenerative diseases like Parkinson’s, Alzheimer’s, major depression, schizophrenia, OCD, addictions, autism, and a drop in quality of life.

N-Acetyl L-Cysteine health benefits

N-Acetyl L-Cysteine (NAC) is a slightly modified version of the sulfur-containing amino acid L-Cysteine. When taken as a supplement, NAC can reduce oxidative stress by replenishing intracellular levels of the natural antioxidant glutathione (GSH). Restoring your cells’ ability to fight damage from reactive oxygen species (ROS).

Conventional medicine has used NAC for decades as an inhaled mucous thinner to treat symptoms of cystic fibrosis. Patients receive intravenous NAC (IV) or orally as a treatment for acute acetaminophen overdose poisoning. NAC quickly restores glutathione levels, averting permanent disability or death.

The nootropics community has recently discovered NAC as a way to suppress inflammation in the brain. NAC prevents oxidative stress on brain cells, eliminates free radicals, restores Brain-Derived Neurotrophic Factor (BDNF), rejuvenates dopamine receptors, and improves overall cognitive function.

NAC can help boost cognition, Long-Term Potentiation for long-term memory formation, short-term and working memory, improve your mood and quell anxiety.

How does N-Acetyl L-Cysteine feel?

Neurohackers report that supplementing with NAC could be the best nootropic they’ve ever used for their brain and overall health. Comments include:

  • Thinking is clearer (less brain fog)N-Acetyl L-Cysteine boosts the feel-good neurotransmitter dopamine
  • Memory improves
  • Concentration and attention improves
  • Less anxiety
  • Less depression
  • Less irritable
  • Mood improves (like a ‘clean high’)
  • Symptoms caused by ADHD meds disappear
  • Obsessive Compulsive behavior decreases
  • Sleep quality improves
  • Energy levels increase
  • Weight maintenance is easier
  • Less flu and colds
  • Skin looks better
  • Feel younger
  • Hangovers are less severe

N-Acetyl L-Cysteine Clinical Research

N-Acetyl L-Cysteine increases dopamine in Parkinson’s Disease

Treatments for Parkinson’s Disease are limited to replacing dopamine in the brain. As well as some medications designed to slow down the disease.

In 2016, researchers at Thomas Jefferson University showed that oxidative stress in the brain could play a critical role in the progression of Parkinson’s. And this stress lowers levels of glutathione, a compound produced in the brain to counteract oxidative stress.

Studies show that N-Acetyl L-Cysteine (NAC) helps reduce oxidative damage to neurons by helping restore the levels of the antioxidant glutathione.

In this study, Parkinson’s patients were placed into two groups. The first group received 50 mg/kg of an intravenous n acetyl cysteine (IV) once per week. And 600 mg of NAC as a supplement twice a day on non-IV days.

The second (control) group received only their standard Parkinson’s treatment. Patients were evaluated at the beginning of the study and again 3 months later.

The evaluation consisted of the Unified Parkinson’s Disease Rating Scale (UPDRS), and a SPECT brain scan which measures the amount of dopamine transporter in the brain.

Compared to controls, the patients receiving NAC had significant improvements in their scores. One of the study authors said, “We have not previously seen an intervention for Parkinson’s disease have this kind of effect on the brain”. This study demonstrated for the first time the direct effect of NAC on the brain’s dopamine system. NAC has the unique ability to enable dopamine neurons to recover their function.[viii]

N Acetyl Cysteine (NAC) alleviates symptoms related to Chronic Obstructive Lung Disease

People suffering from chronic obstructive pulmonary disease (COPD) may experience long-term oxidative damage and inflammation of lung tissue. And lack of oxygen to the brain can have a severe impact on memory.

In addition, any chronic lung disease, such as bronchitis, can cause airways to constrict. This inflammation may lead to shortness of breath or coughing. Research suggests that taking the potent antioxidant N-Acetyl Cysteine (NAC), dietary supplements can help improve symptoms related to COPD, chronic bronchitis, and its complications, and improve lung function.

N-Acetyl L-Cysteine repairs Traumatic Brain Injury

Traumatic brain injury (TBI) is a major public health issue affecting 69 million people worldwide each year.[ix] TBI can be caused by sports injuries, work accidents, car and motorcycle accidents, falls, and your wife hitting you over the head with a frying pan.

Many survivors end up with long-term or even permanent neurocognitive dysfunction. Affecting cognition, motor function (movement) and personality. These disabilities are estimated to cost $26 billion in lifetime medical costs and $631 billion in quality of life lost.[x]

A major cause of TBI comes from blast exposure on the battlefield. Symptoms are similar to other causes of TBI; dizziness, hearing loss, headache, memory loss, sleep issues, and neurocognitive dysfunction.

In a brain subjected to TBI there is glutamate toxicity, free-radical injury to brain cells, electrolyte imbalances, mitochondrial dysfunction, inflammation, apoptosis (cell death) and stroke.[xi][xii]N-Acetyl L-Cysteine is used to treat Traumatic Brain Injury

This double blind, placebo-controlled study was conducted with 81 active duty service members at a forward deployed field hospital in Iraq. All service members in this study were exposed to significant ordinance blast and met the criteria for TBI.

Service members were randomly assigned to receive either a placebo or N-Acetyl L-Cysteine (NAC) for 7 days. The resolution after 7 days of all the TBI symptoms listed above was the main outcome measure of this study.

The researchers concluded that NAC was a safe pharmaceutical countermeasure of blast-induced TBI. And that further work on long term outcomes and the potential use of NAC in civilian TBI is warranted.[xiii]

N-Acetyl L-Cysteine helps alleviate depression

Both depression and bipolar disorder are complicated by glutathione depletion. The researchers in this double-blind, multicenter, placebo-controlled study worked with 75 subjects with bipolar disorder.

Subjects received 1 gram of NAC twice daily for 24 weeks. NAC treatment caused a significant improvement with depression with those using NAC.

The researchers concluded, “NAC appears a safe and effective augmentation strategy for depressive symptoms”. In this case with people suffering from bipolar disorder.[xiv]

N-Acetyl L-Cysteine Recommended Dosage

N-Acetyl L-Cysteine dosage recommendationsN-Acetyl L-Cysteine (NAC) suggested dosage for cognitive benefit is 500 mg 3-times per day.

Clinical studies have found that doses up to 2,000 mg per day are safe and effective.

And one German study showed the safety of 2,800 mg per day for 3 months in patients with cystic fibrosis.[xv]

NAC has also proven effective against seasonal influenza and flu-like illnesses. One large study of older adults in Italy took 600 mg of NAC twice daily for 6 months. Only 25% of those adults who used NAC experienced flu-like episodes compared to 79% in the placebo group.[xvi]

N-Acetyl L-Cysteine Side Effects

N-Acetyl L-Cysteine (NAC) is the N-acetyl form of one of the naturally occurring amino acids of the body, L-Cysteine.

NAC is a slightly modified version of the sulfur-containing amino acid L-Cysteine. So NAC in powder form can have an unpleasant smell.

Very rarely can NAC cause nausea, vomiting, diarrhea or constipation. Even more rare are rashes, fever, headache, drowsiness, low blood pressure and liver problems.

Side effects can be a result of very high doses of NAC. And if you have a genetic condition called Cystinuria do not use NAC. This rare condition causes stones to form in the kidneys, ureter and bladder from cysteine. NAC is the N-Acetyl form of Cysteine.

One study has also found that long-term use of high-dose NAC can deplete your body’s stores of zinc. So if you are using NAC everyday you should also supplement with zinc and low dose copper.

Where to buy N-Acetyl L-Cysteine

N-Acetyl L-Cysteine (NAC) is available in powder, tablet and capsule form. NAC capsules and tablets were usually 500 mg.

Where to buy: I highly recommend: Life Extension – NAC

NAC was in short supply because on July 23, 2020, the FDA sent a warning letter to Purple Biosciences LLC about its NAC product. And asserted that NAC was illegally sold as a dietary supplement because it was approved as a drug September 14, 1963.  Several other letters were sent to supplement manufacturers. Resulting in NAC being difficult to find on Amazon or many of the other sites that used to sell NAC.

Several lawsuits were filed against the FDA. And NAC has since become easier to find in the supplements sections of online stores.

Nootropics Expert Recommendation

N-Acetyl L-Cysteine (NAC) 500 mg, 3-times per day

Nootropics Expert Tested and ApprovedI highly recommend using N-Acetyl L-Cysteine (NAC) as a nootropic supplement.

Your body does synthesize some L-Cysteine from methionine. And you can get L-Cysteine from foods such as dairy, poultry, pork, and some grains and nuts.

But most of us don’t get enough N-Acetyl L-Cysteine from our diet. So supplementation will help. And N-Acetyl L-Cysteine is a highly bioavailable form of L-Cysteine. So you should feel its effects faster.

NAC is helpful for most neurohackers to improve mood, memory, cognition, and concentration. And NAC helps alleviate brain fog, anxiety, and irritability.

NAC is especially helpful to those dealing with Obsessive Compulsive Disorder. And stacked with ADHD meds, NAC helps alleviate some of the negative side effects associated with stimulants.

If you can still find it, you can safely use up to 1,800 mg of NAC per day. The usual dose for cognitive improvement is 500 mg dosed 3 times throughout your day.

I recommend N-Acetyl L-Cysteine (NAC) from : Life Extension – NAC

As an Amazon Associate I earn from qualifying purchases. This post may also contain other affiliate links and I will be compensated if you make a purchase after clicking on my links.

[i] Neuwelt E.A., Pagel M.A., Hasler B.P., Deloughery T.G., Muldoon L.L. “Therapeutic efficacy of aortic administration of N-acetylcysteine as a chemoprotectant against bone marrow toxicity after intracarotid administration of alkylators, with or without glutathione depletion in a rat model.” Cancer Research. 2001 Nov 1;61(21):7868-74 (source)

[ii] Scalley R.D., Conner C.S. “Acetaminophen poisoning: a case report of the use of acetylcysteine.” American Journal of Hospital Pharmacy. 1978 Aug;35(8):964-7. (source)

[iii] Neergaard L. “Most Popular painkiller is lead cause of acute liver failure” National AIDS Treatment Advocacy Project natap.org Dec. 25, 2005 retrieved June 17, 2016 (source)

[iv] Eakin K., et. Al. “Efficacy of N-Acetyl Cysteine in Traumatic Brain Injury” PLoS One. 2014; 9(4): e90617. (source)

[v] Hashimoto K., Tsukada H., Nishiyama S., Fukumoto D., Kakiuchi T., Shimizu E., Iyo M. “Effects of N-acetyl-L-cysteine on the reduction of brain dopamine transporters in monkey treated with methamphetamine.” Annals of the New York Academy of Sciences. 2004 Oct;1025:231-5. (source)

[vi] Saleh A.A.S. “Anti-neuroinflammatory and antioxidant effects of N-acetyl cysteine in long-term consumption of artificial sweetener aspartame in the rat cerebral cortex” The Journal of Basic & Applied Zoology Volume 72, October 2015, Pages 73–80 (source)

[vii] European College of Neuropsychopharmacology (ECNP). “Amino acid offers potential therapeutic alternative in psychiatric disorders.” Science Newsline Medicine sciencenewsline.com October 7, 2013 Retrieved June 18, 2016 (source)

[viii] Monti D.A., Zabrecky G., Kremens D., Lian T.W., Wintering N.A., Cai J., Wei X., Bazzan A.J., Zhong L., Bowen B., Intenzo C.M., Iacovitti L., Newberg A.B. “N-Acetyl Cysteine May Support Dopamine Neurons in Parkinson’s Disease: Preliminary Clinical and Cell Line Data.” PLOS ONE, 2016; 11 (6): e0157602 (source)

[ix] Dewan M.C., Rattani A., Gupta S., Baticulon R.E., Hung Y., Punchak M. Agrawal A., Adeleye A.O., Shrime M.G., Rubiano A., Rosenfeld J.V., Park K.B. “Estimating the global incidence of traumatic brain injury” Journal of Neurosurgery Volume 130; Issue 4 (Apr 2019) (source)

[x] “Traumatic Brain Injury” A Roadmap for Accelerating Progress 2022 Chapter 2 National Academies Press (source)

[xi] Yi J.H., Hazell A.S. “Excitotoxic mechanisms and the role of astrocytic glutamate transporters in traumatic brain injury.”Neurochemistry International. 2006 Apr;48(5):394-403 (source)

[xii] Farkas O., Povlishock J.T. “Cellular and subcellular change evoked by diffuse traumatic brain injury: a complex web of change extending far beyond focal damage.” Progress in Brain Research. 2007;161:43-59. (source)

[xiii] Hoffer M.E., Balaban C., Slade M.D., Tsao J.W., Hoffer B. “Amelioration of acute sequelae of blast induced mild traumatic brain injury by N-acetyl cysteine: a double-blind, placebo controlled study.”PLoS One. 2013;8(1):e54163. (source)

[xiv] Berk M., Copolov D.L., Dean O., Lu K., Jeavons S, Schapkaitz I., Anderson-Hunt M., Bush A.I. “N-acetyl cysteine for depressive symptoms in bipolar disorder–a double-blind randomized placebo-controlled trial.” Biological Psychiatry. 2008 Sep 15;64(6):468-75 (source)

[xv] Dauletbaev N., Fischer P., Aulbach B., Gross J., Kusche W., Thyroff-Friesinger U., Wagner T.O., Bargon J. “A phase II study on safety and efficacy of high-dose N-acetylcysteine in patients with cystic fibrosis.” European Journal of Medical Research. 2009 Aug 12;14(8):352-8. (source)

[xvi] De Flora S., Grassi C., Carati L. “Attenuation of influenza-like symptomatology and improvement of cell-mediated immunity with long-term N-acetyl cysteine treatment”. The European Respiratory Journal. 1997 Jul;10(7):1535-41. (source)

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Join The Discussion - 518 comments

Jaf
July 25, 2020

Any ideas on whether its safe to take glutathione supplements at the same time as NAC?

    David Tomen
    July 26, 2020

    Jaf, I don’t think it’s contraindicated. But too much of anything is not a good idea.

Mick
July 25, 2020

Hi David,
I started using NAC about four months ago for withdrawal from antidepressant Nortriptyline (Allegron). You recommended NAC to treat the withdrawal as Traumatic Brain Injury (TBI). I went down from 100mg of allegron to 75mg. I don’t want to decrease the dosage any more, I like the way I feel at the moment. But I would like to add the final two nootropics to my stack – Pine Bark Extract that you recommended at the consultation we had and Vitamin D because my Vitamin D level is a bit low. My stack at the moment is very big and I don’t want to take something that I don’t need. So I was thinking, because I don’t withdraw from antidepressant any more to stop taking NAC. But on the other hand I don’t want to feel worse by stopping it. As I mentioned my stack is very big, and I’m not sure how to see if NAC gives me any benefit at the moment. Even if it helps a little bit and I’ll stop it I don’t think I will be able to tell, because of the other nootropics that I take.

David what do you think the best thing for me to do in this situation?

Any help is greatly appreciated.

    David Tomen
    July 26, 2020

    Mick, you know I’m a big fan of NAC and would continue to use it. Because it’s a precursor to the synthesis of glutathione which is a potent antioxidant, anti-inflammatory and free radical scavenger. And NAC modulates glutamate levels and dopamine release in your brain. Those are all pretty convincing reasons to use it every day. Don’t you think?

      Mick
      July 27, 2020

      I think it’s a peace of mind continuing with NAC, even if it makes me feel a little bit better in my situation at the moment. By stopping it I’m risking feeling a bit worse than I do now, so I think it’s worth it.

      Thanks David.

Chris
June 14, 2020

Hi David,

If my whey protein isolate powder (NOW Sports, so reputable) contains 728mg L Cysteine per serving, and I consume 2 servings per day, is it ok to take NAC separately, 600mg 3 times a day as recommended?

I didn’t notice the whey protein contained L Cysteine until after I bought the NAC. I also take 30mg zinc with 2mg copper as recommended.

I’m wondering if NAC on top of L Cysteine basically means I am then taking too much ‘Cysteine’ in general, as 2 servings of the whey protein is approx 1,500mg, and the 1,800mg NAC means a total of 3,300mg per day…

Thank you!

Chris

    David Tomen
    June 15, 2020

    Chris, one German study showed the safety of 2,800 mg of NAC per day for 3 months in patients with cystic fibrosis. But I’d check the “side effects” section above in this review to keep an eye out for symptoms. Because side effects from L-Cysteine are usually associated with high doses. If you don’t experience any of those side effects (including getting your liver checked) then you should be OK.

      MR SAM
      July 14, 2020

      HI DAVID ,,would like to know if I take supplement with NAC will give the same results of l cysteine ..I need to know as there is amino acid supplements contain L cysteine wonder if it gives the same effect ,,and if I take it for long term it will have any side effects,,

        David Tomen
        July 15, 2020

        Mr. Sam, my understanding is an acetyl group was added to cysteine to help make it more bioavailable and so it could cross the blood-brain barrier. I do not think you’ll get the same nootropic benefit that’s provided by NAC if you just use L-Cysteine.

Shivansh Batra
June 10, 2020

Hello David,
After reading most of your post, i have a confusion i.e. I feel Ala, NAC and Taurine are interconnected to each other either because on glutathione or cysteine.
Does it mean if i use ala then taking nac is unnecessaryn or vice-versa.
Secondly, I need recommendation from you which nootropics i use to increase mental energy. My blood pressure is generally normal but on lower side. My feets are also cold in summer time.
I have used many nootropics for energy as recommended in your post but still nothing helped me out. I am lacking basic mental energy and motivation. I tried up till now mct oil, alcar, ala, pine bark extract for energy.
To fight this mental fatigue only krill oil, nalt help a bit. I don’t know what’s the problem.
Do you have any suggestions?

Regards

Shivansh Batra

    David Tomen
    June 12, 2020

    Shivansh, Alpha Lipoic Acid, NAC and Taurine are all very different nootropic supplements. For example, cysteine provided by NAC helps in the synthesis of Taurine. But it has other nootropic functions as well.

    You’ve already hinted at a clue on what may be contributing to your mental fatigue. With krill oil it means you’re low in DHA. And with NALT it means you’re low in dopamine and norepinephrine. Both have an effect on energy levels. Please see dosage recommendations including timing during the day for both DHA and NALT here on Nootropics Expert.

    A basic energy stack (https://nootropicsexpert.com/best-energy-supplements-to-buy/) includes ALCAR, Alpha Lipoic Acid, CoQ10 and PQQ. That stack ensures your mitochondria can make adequate ATP which is your most basic and fundamental source of energy.

    Motivation is associated with the dopamine pathway. But you need more than to simply boost dopamine if you want to activate that pathway. You also need a nootropic to activate AMPA receptors. Which is explained in this post: https://nootropicsexpert.com/hacking-motivation-with-nootropics/

    The key to making this all work is using adequate dosages and the right timing during your day. You’ll find that info in each of the relevant reviews. Let me know if you require further clarification.

Amy
May 15, 2020

My daughter takes 2400 mg NAC daily (split into two doses) with extra vitamin C to treat a lung problem. She recently started an antidepressant, Lexapro, and seems to be worse. Her symptoms mimic a mild serotonin syndrome. I’ve had serotonin syndrome five separate times from all different meds. I am extremely prone to it. I have yet to find a doctor who has any knowledge on this to help me with this problem as I also have four rear immune and neurodegenerative conditions that need treating but because of this I can’t take the meds I need. I’m hoping you can help me with two things: do you know any specialist that might be able to help me with the too prone to serotonin syndrome issue or have knowledge on it and/or do you know if the combo of an antidepressant and high dose NAC could cause serotonin syndrome? I have read that it affects glutathione and dopamine and serotonin but couldn’t find the direct effect on serotonin. I have found in research that it increases the minimal effective dose of Lexapro so definitely interacts. I appreciate any help you can give in this matter. Thank you.

    David Tomen
    May 16, 2020

    Amy, I am not aware of any direct contraindication for NAC with Lexapro. But be aware of two things: 1. Lexapro inhibits the liver enzyme CYP2D6 which will increase the effectiveness of anything that is normally metabolized by that enzyme. So I suspect that the already high dose of NAC is even higher when using Lexapro.

    2. The other thing is high dosages of NAC suppress zinc levels. Zinc is needed as a cofactor in the synthesis of serotonin.

    It sounds like such a high dose of NAC with Lexapro is throwing some major neurotransmitters out of balance. Which will cause side effects and some could mimic Serotonin Syndrome.

    I suggest you cut back on your NAC dose and see how that works. The maximum recommended dose for NAC is 1,800 mg and that’s usually split into 3 doses per day. And add a zinc supplement along with a low dose copper supplement. More on zinc here: https://nootropicsexpert.com/zinc/

Paul
March 20, 2020

Hi David ,

I did a Genova methylation panel to check on my current levels, and cysteine came back very low and taurine very high. I supplement with 3000mgs of oral NAC daily divided 3 times thorough out the day to try and boost Glutathione levels. I also supplement Taurine 1000mgs 2 x a day. My physician seems to think the cysteine is converting to taurine somehow. Have you heard of this? He wants me to stop the oral NAC and start transdermal 3 x a day. Just wondering what your thoughts are on the NAC taurine interaction. Thanks.

    David Tomen
    March 20, 2020

    Paul, Taurine is naturally derived from cysteine in your pancreas. Using both NAC and taurine will influence taurine levels in your system.

Delia
March 18, 2020

David, can I continue taking my multivitamins and other supplements like L-Glutamine with NAC 1000mg?

    David Tomen
    March 19, 2020

    Delia, yes you can and it’s a great addition to your stack. Esp. if you want to support your immune system.

NN
March 15, 2020

Greetings

I am curious, David, if you find it possible that n-acetylcysteine could exacerbate or even induce, a cobalamin deficiency. The reason I ask is that shortly after consuming NAC over a period of two days (in total, 1700mg) I began to present with symptoms of b9/b12 deficiency. I did some cursory research in the sequence of glutathione production and found that vitamins b6,9,12 are all involved in the production of glutathione.

Now, being that NAC is a glutathione precursor, do you think that this could have caused a cobalamin deficiency or exacerbated a deficiency I had already had (but was without symptoms)?

    David Tomen
    March 16, 2020

    Nathan, it was likely a deficiency you were already experiencing and did not know it was happening.

    I tell almost every single person I consult with to add a B-Complex supplement to their stack. Because most of us are deficient in 2 or more of the B-Vitamins, magnesium, lithium, iodine, and other critical vitamins and minerals. Being low in just one of them affects a ton of stuff going on in your body and brain.

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