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N-acetylcysteine (NAC) Crash

Messages
54
I started taking N-acetylcysteine a couple of weeks ago in an attempt to fix my insomnia. I slept sooooooo much better for the three days that I took it, and my brain function and mood improved too.

However, I then experienced a major flare-up of fatigue and inflammation, the kind of which I haven't had since 2012. I don't think it's a coincidence either because nothing else had changed and I've read that others have experienced similar.

Has anyone else gone through a 'NAC crash' and if so, how long did it take to wear off? Was there anything which helped you to get over it?
 

drmullin30

Senior Member
Messages
217
Per Fredd NAC will drive b12 out of cells and stop methylation and create a methyl trap.

Also, if you have a CBS upregulation SNP or high sulfur, NAC will send your sulfites high and cause the problems you're experiencing.

I used to use it for glutamate control and to raise glutathione and it worked very well for this but I did notice a damping effect on energy, and methylation in general. When I started Fredd's protocol or advanced methylation protocol I eliminated it and haven't used it in several years now.

I would imagine that if you raise your intake of b12, folate and/or the deadlock quartet, this should clear up within a few weeks.
 
Messages
54
Per Fredd NAC will drive b12 out of cells and stop methylation and create a methyl trap.

Aaaaah thank you! I didn’t know that. That explains why I feel so anaemic and low on B12 at the moment. Glad to know that supplements should help to pull me out of this ( even if they do worsen the insomnia).
 
Messages
54
NAC is a sulfur/thiol. Do you know if you have issues with those? I can still eat them once in a while but if I do so too often I get migraine headaches.

Here's something on that: https://www.livingnetwork.co.za/chelationnetwork/food/high-sulfur-sulphur-food-list/

I wouldn't know to be honest, it's something I've never thought about.

I feel much better this morning for taking some B12 so I suspect that was the issue in this case.

That said, I really appreciate the link that you've sent me as I still need to find the root cause of the insomnia and that website has some interesting approaches that I haven't tried yet.
 

Pyrrhus

Senior Member
Messages
4,172
Location
U.S., Earth
Has anyone else gone through a 'NAC crash' and if so, how long did it take to wear off?

I talk about my "NAC hell" in this thread:
https://forums.phoenixrising.me/threads/glutathione-causing-anxiety-irritability.81246/#post-2304206

Per Fredd NAC will drive b12 out of cells and stop methylation and create a methyl trap.

Actually, that's just a myth. NAC, which is just a shelf-stable form of the common amino acid cysteine, boosts glutathione, which is actually required for some forms of B12 to be used inside a cell.

Without sufficient glutathione, the cell will not be able to utilize these forms of B12. The details are complex, but you can read more in the section titled "Early Steps in the Cytosolic Processing of Cobalamin" in this paper:
https://www.jbc.org/content/288/19/13186.full.pdf

Hope this helps.
 

drmullin30

Senior Member
Messages
217
Actually, that's just a myth. NAC, which is just a shelf-stable form of the common amino acid cysteine, boosts glutathione, which is actually required for some forms of B12 to be used inside a cell.

Wow @Pyrrhus I hope you're right! I miss NAC! It was always very calming for me and helped my sleep and anxiety but it's not part of the advanced protocol for some very convincing reasons laid out in many pages of posts by Fredd. I'm going to revisit this issue.

I did find that some of the methyl trap symptoms were starting to show up when I was using NAC. A lot the stuff Fredd talks about, especially skin and digestive problems.
 
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Messages
54

Thank you! That's exactly the kind of post I was looking for to prove that I wasn't going crazy. I think I must've missed it in my searches due to the different ways it can be spelled/ the fact that NAC is too short to search. I had some of the same symptoms, namely the breathlessness and severe fatigue. I also lost my appetite and felt as though I was losing weight. Funnily enough, it actually improved my brain fog and insomnia though.

Interesting to read that the effect eventually wore off for you and that you were able to tolerate it. I'm not sure if I could stick it out for that long, as lovely as the brain and sleep benefits were.

I'm feeling soooooo much better today for coming off it and for a second day of B12. It makes me wonder if I could tolerate the NAC if I took B12 at the same time, but now that I'm slowly getting some balance back I don't want to risk upsetting things again.
 

godlovesatrier

Senior Member
Messages
2,545
Location
United Kingdom
I just wanted to give an update on my titration with NAC.

I was crashing badly taking 500mg even with breaks and what not. So I eventually got a powdered bag of NAC and started taking 100mg doses. I titrated up over about 3 or 4 weeks. Now I'm taking 3000mg a day without any effects that I can sense. Certainly zero fatigue and no crashes.

Just in case others were also struggling with this or had in the past, it seems possible to get to the higher doses but only with very gradual increases. Co factors might be a thing too.
 

Hip

Senior Member
Messages
17,824
Just as alpha lipoic acid is a chelator of inorganic mercury, N-acetyl-cysteine causes increased excretion of organic mercury (like methylmercury). Ref: here.

So I wonder if those with high levels of methylmercury might experience adverse effects from NAC?


This thread details someone who developed "burning brain" from NAC, which they speculated was due to mercury.
 

Pyrrhus

Senior Member
Messages
4,172
Location
U.S., Earth
I was crashing badly taking 500mg even with breaks and what not. So I eventually got a powdered bag of NAC and started taking 100mg doses. I titrated up over about 3 or 4 weeks. Now I'm taking 3000mg a day without any effects that I can sense. Certainly zero fatigue and no crashes.

Congratulations on sticking it out!

Just as alpha lipoic acid is a chelator of inorganic mercury, N-acetyl-cysteine causes increased excretion of organic mercury (like methylmercury). Ref: here.

The chelation potential of cysteine and acetyl-cysteine only becomes relevant at supraphysiological doses higher than 1000mg.

Below roughly 1000mg, cysteine is mainly used in protein synthesis, just as evolution 'intended'.
 

Hip

Senior Member
Messages
17,824
The chelation potential of cysteine and acetyl-cysteine only becomes relevant at supraphysiological doses higher than 1000mg.

Below roughly 1000mg, cysteine is mainly used in protein synthesis, just as evolution 'intended'.

That's interesting.

I recently tried some high dose NAC, 2 grams twice daily, and found it caused an overstimulation effect (but only during the night), making it hard to sleep; and it also caused perturbed strange sleep. This was significant enough for me to abandon my experiment with high dose NAC.

At doses of 600 mg daily, I never noticed these side effects.
 

Pyrrhus

Senior Member
Messages
4,172
Location
U.S., Earth
I recently tried some high dose NAC, 2 grams twice daily, and found it caused an overstimulation effect (but only during the night), making it hard to sleep; and it also caused perturbed strange sleep.

That's really interesting. Strangely, there is currently a fad among psychiatrists to prescribe high-dose NAC as a sedative!

I remember that @Valentijn took high-dose NAC on a daily basis and reported that it helped her with the "wired-but-tired" feeling.

Definitely interesting about the 1000mg level. That's per say @Pyrrhus ?

1000mg is just a rough estimate based on the average dietary intake of cysteine, which is somewhere between 600mg-1200mg. (1000mg NAC = 740mg cysteine)
 

Cipher

Administrator
Messages
838
I recently tried some high dose NAC, 2 grams twice daily, and found it caused an overstimulation effect (but only during the night), making it hard to sleep; and it also caused perturbed strange sleep. This was significant enough for me to abandon my experiment with high dose NAC.

This is pure speculation on my part, but perhaps the overstimulation stems from decreased levels of glycine in the brain as the body combines cysteine with glycine (and L-glutamate) to produce glutathione. Taking extra glycine might counteract this hypothetical decrease in brain glycine levels and ameliorate the overstimulation. Supplemental glycine have been shown to improve sleep quality in humans. However, if it's the increase in glutathione that's somehow causing the overstimulation, then taking extra glycine could instead increase the overstimulation. Slowly increasing the NAC dose over time might also be an idea, like @Pyrrhus did.
 
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godlovesatrier

Senior Member
Messages
2,545
Location
United Kingdom
Really interesting point about glutathione levels. I've just realised tonight that when I take one thing in isolation and it gives me anxiety (lots of things do this) maybe it was increasing my glutamine levels too much and therefore I had no chance of ever finding a therapeutic dose etc because it was never going to work without supplemental nac and glycine. I'm now doing 4g of glycine 4x a day plus 600mg nac 3x a day and I do feel very stable mood wise. No anxiety and no depression. I mean hell I even crashed really badly in the night and yet apart from an hour or so thismorning my moods remained stable. Which is starting to make me wonder is it these two things.

Because before I started this new protocol I was taking thiamine. Gylcine and nac (at lower doses) and there was no anxiety and no depression etc. Which was kind of a first. I was actually feeling really good!

Anyway @YippeeKi YOW !! Just mentioned gaba and glutamine on another thread and someone else mentioned it last week and now people have on this thread as well. So I think that might be it. For me anyway.
 

YippeeKi YOW !!

Senior Member
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16,047
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Second star to the right ...
Anyway @YippeeKi YOW !! Just mentioned gaba and glutamine on another thread and someone else mentioned it last week and now people have on this thread as well. So I think that might be it. For me anyway.
It sounds like it might be ....


I'll get back to you later today or early tomorrow .... I've really hit a thick-headed fatigue wall and need to do a short-ish time out ....

Glycine always made me worse when I was just at the beginning of The Troubles, but then almost all isolated, hydrolyzed aminos had a negative excitatory effect on me, the worst being glutamine/glutamic acid, as did everything else that was supposed to help, like NAC, theanine, taurine, all herbs used for sleep from hops to passion flower an valerian and everything in between (they metabolize thru the sa,e P450 liver enzyme channels that benzos do) and scores of others I can't recall right now.

Back later ... hang in !!!