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Anger triggered by Xifaxan (Rifaxamin)?

Messages
10
I'm wondering if anyone has ever had anger or extreme irritability as a reaction to Xifaxan (Rifaximin), especially within minutes of taking the pill?

I have used Xifaxan several times over the years, and it has given me amazing results almost every time. It improves my brain fog, fatigue, depression, and so on. I have always tolerated it well. Until this time...

This time, as always, I got major improvements to my brain fog and fatigue within hours. And improvements continued for several days. But after a week or two, I started becoming very irritable and often extremely angry. Something as simple as stubbing my toe would set me off to where I'd have to throw something, shout curse words, etc.

I had been taking Adderall to help me get by for a few months before I got the Xifaxan prescription. Adderall definitely causes me to be irritable and angry at times, especially when titrating up. So at first I thought that I was probably just overstimulated because my current dose of Adderall became too much once Xifaxan addressed underlying issues. So I tapered off Adderall, but the irritability and anger episodes continued.

Eventually, I realized that the anger and irritability were triggered every time I took the Xifaxan pill. And by the time the anger was just about worn off, it would be time for me to take another Xifaxan pill. Three times per day. I'm certain that the reaction started within five minutes of swallowing the pill.

Then eventually, after a few more weeks of taking Xifaxan, the anger/irritability reaction stopped. But at that same point in time, I also lost all the benefits that I had gotten. My brain fog and fatigue were back in full force, and I had to titrate back up on Adderall.

I wonder if anyone else has experienced something like this. Curious how things turned out and if anyone has advice.
 

Hip

Senior Member
Messages
18,045
It may be that the bacterial die-off caused by each dose of rifaximin leads to more inflammation in the gut, which then by the well-known vagus nerve gut-to-brain pathway, triggers inflammation in the brain, leading to the mental symptoms of irritability and anger.

Here are some treatments I found useful for my own irritability symptoms.

Are you taking good amounts of probiotics after each course of rifaximin? Rifaximin will kill good as well as bad bacteria in the gut, and may thus allow bad bacteria to dominate over good (this is called dysbiosis).
 

sb4

Senior Member
Messages
1,678
Location
United Kingdom
Rifaximin will kill good as well as bad bacteria in the gut, and may thus allow bad bacteria to dominate over good
As far as I understand it Rifaximin is limited to the small intestines. I have heard that there is bacteria in the SI but it is mostly sterile so would killing good bacteria be very significant with this drug.
 

Hip

Senior Member
Messages
18,045
As far as I understand it Rifaximin is limited to the small intestines.

Rifaximin it not absorbed into the system, and travels along the small and then large intestine, and only has an effect on the bacteria there. The small intestine is usually fairly sterile (unless you have SIBO), so it will usually only be working in the large intestine.
 

ljimbo423

Senior Member
Messages
4,705
Location
United States, New Hampshire
As far as I understand it Rifaximin is limited to the small intestines. I have heard that there is bacteria in the SI but it is mostly sterile so would killing good bacteria be very significant with this drug.

I wonder about this too. Their are dramatically less bacteria in the small intestine than the large intestine but my feeling is they are important. So a proper balance, think, would still be important.
 

ljimbo423

Senior Member
Messages
4,705
Location
United States, New Hampshire
The small intestine is usually fairly sterile (unless you have SIBO), so it will usually only be working in the large intestine.

Hey Hip- I did a lot reading about Rifaximin before I took 2 courses a couple of years ago. If I remember right, bile is needed to activate it and most bile is reabsorbed at the end of the small intestine.

So the Rifaximin becomes almost completely deactivated in the colon.
 

Hip

Senior Member
Messages
18,045
Hey Hip- I did a lot reading about Rifaximin before I took 2 courses a couple of years ago. If I remember right, bile is needed to activate it and most bile is reabsorbed at the end of the small intestine.

So the Rifaximin becomes almost completely deactivated in the colon.

I did not know about the bile thing. The quotes I just found (see below) suggest rifaximin may be less effective in the colon, but that it still works in the colon too.


Some observations suggested that rifaximin may be more effective in the treatment of infections in the small intestine, because of the higher concentration of bile in this region than in the colon, as bile acids appear to solubilize rifaximin on a dose-dependent manner, increasing the drug’s antimicrobial effect.
Source: here

As a result of bile acid solubility, its antibacterial action is limited mostly to the small intestine and less so the colon.
Source: here
 
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