thiamine paradox

With Thiamine Paradox Symptoms Patience Is Key

Print Friendly, PDF & Email

I wanted to share my experience going through thiamine paradox so that others may find hope as they navigate the process. In November of 2019, my life was completely flipped upside down. My full story is here, but briefly, I had taken an antibiotic called Tinidazole, the less popular but almost identical sister drug to Metronidazole. Within days of taking the antibiotic I began to experience frightening symptoms like loss of mobility in my hands, heart palpitations and intense feelings of depression and doom. Less than two weeks later, I went into surgery to get my wisdom teeth removed and was put on a course of penicillin for two weeks.

Within weeks, my health was in a total spiral. I began to experience constant bouts of tachycardia and panic, low blood sugar, dizziness, blurry vision and the inability to sleep. I went from somebody who sleeps 8 hours a night to sleeping for less than an hour on various nights. When sleep did come, I was jolted awake in a panic attack. At times, I was feeling symptoms that mimicked asthma…it was like I couldn’t breathe.

I had no idea what was going on. Multiple trips to the ER did nothing. I continued to get worse. It wasn’t until I traced back what drugs I had taken that I made my way to a Facebook group called “Metronidazole Toxicity Support Group.” It was in that group that I discovered that thousands of others were dealing with the same set of symptoms caused by this horrendously neurotoxic antibiotic. I had known for years that one should avoid fluoroquinolone antibiotics, but research has shown that metronidazole and others in its class present some of the same catastrophic side effects.

Through her own research and contact with Dr. Lonsdale and Dr. Marrs, the founder of the group discovered that metronidazole and other drugs in its class block thiamine in the body. The symptoms of the toxicity mimic those of Wernicke’s encephalopathy.

The solution? Take thiamine.

I thought it was going to be an easy fix. It wasn’t.

Like many posts on Hormones Matter, the topic of paradox frequently comes up, and I am the perfect case study.

In retrospect, I had longstanding symptoms of mild beriberi for a lot of my life. I was constantly dealing with low blood pressure and strange heart symptoms that date back to my teenage years. I grew up eating a typical American diet and started drinking large amounts of coffee in my teens. I loved sugar.

With longstanding thiamine deficiency, the human body changes its chemistry to adapt and survive. When thiamine is reintroduced and things get turned back, your body goes haywire until the chemistry can normalize.

For me, it took three attempts. Every time I would start even the tiniest dose of thiamine HCL, I would erupt in panic, tachycardia, feelings of “seizures” and doom and gloom, chest tightness and head pressure. It was akin to the feeling when somebody knows that they ingested way more marijuana than they should have. Sheer terror. When I took too much one time, I almost landed in the ER because I thought for sure that I was going into cardiac arrest.

My first attempt was in January 2020. I failed miserably and stopped because of the side effects. But I wasn’t getting better and my health continued to spiral. I tried again in March 2020 and made it for 2 weeks before dropping out again. I would crumble pills to get just a little thiamine HCL in my system and I would still feel like a total wreck.

Finally, on my third attempt in May 2020, I made it.

The solution is to start LOW and SLOW. I found a company in the UK that has a liquid form of thiamine HCL that allowed me to do this. I started with 10 mg per day and gradually increased by 10-20 mg over the course of many weeks. I also spread my dose out throughout the day. Dr. Lonsdale predicted the paradox will lift within a month, but for me, it took a bit longer. Within 8 weeks I began to notice that I could safely take a 100mg thiamine HCL pill without experiencing too many symptoms. It continued to get better with time.

Now, almost a year later, I’m taking 300-400mg of thiamine HCL a day and mixing in benfotiamine and allithiamine. In the last 6 months, my health has slowly started to trend upward. I’ve added in a B complex at times and I’m also working on my B12. The heart palpitations are significantly better, I’m less prone to panic attacks than I have been in years, and my brain fog has lifted. What I’m left with is some slight dizziness (though it is significantly better), blurry vision that waxes and wanes, and my blood sugar is still presenting some issues. Still, I feel like I’m trending in the right direction and that things continue to slowly improve.

My advice for those of you encountering paradox symptoms is this: BE PATIENT. It sucks. But the rewards on the other end are so worth it. I would also advise you to dramatically increase your potassium through food. This didn’t eliminate the paradox feelings entirely but it did help reduce them.

We Need Your Help

More people than ever are reading Hormones Matter, a testament to the need for independent voices in health and medicine. We are not funded and accept limited advertising. Unlike many health sites, we don’t force you to purchase a subscription. We believe health information should be open to all. If you read Hormones Matter, like it, please help support it. Contribute now.

Yes, I would like to support Hormones Matter. 

Photo by Aron Visuals on Unsplash.

This article was publish originally on January 26, 2021. 


  1. Hello! I have a question regarding the paradoxical reaction.
    I have been suffering with POTS symptoms for the last four years now. I don’t have an official diagnosis because I can’t get my doctors to take me seriously.
    My symptoms are rapid heart rate when I go from sitting to standing (60’s sitting and up to 130’s when standing) severe exercise intolerance, severe fatigue and weakness, chest pressure and pain, burning in my arms and legs quickly after using them for the simplest of tasks, heat intolerant, cold intolerant, chronic vitamin deficiencies… I am completely bedridden now. (Before i started ttfd, i was functional while taking a beta blocker)
    I just started TTFD about 8 days ago. I started with 50mg for a couple days and felt no reaction, so I increased my dose to 150mg and still felt ok. Two or three days later I upped the dose to 200mg of TTFD and within that short time span, my body has crashed.
    Just last week, I was at least able to get up and function, now I feel like I have lost all the progress I have made over the years. I’d like to add, I take 100mg of Atenolol a day, which has kept me functional and my heart rate manageable for a while now. My body is not responding to my beta blocker anymore.
    In my desperate attempt to get some normalcy back in my life, (I got sick with these symptoms in 2019 right before covid started) I purchased TTFD because I am sure with all of my other deficiencies, my thiamine status is sure to be low. I have been reading everyone’s really inspiring story’s of recovery following thiamine repletion and wanted to give it a try. Well, I think I dove in to quickly, and now I think I’m having the paradoxical reaction.
    I made sure to take the TTFD alongside magnesium, Potassium and a methylated B Complex.
    I guess my question is, how long will this last? Will I return to my previous baseline of symptoms? I stopped the TTFD for now because this is unbearable for me. I have gone from functional and able to work, to completely useless in a matter of days.
    This is just a guess, but I am thinking that my magnesium was probably low to begin with, and jumping into a high dose of TTFD could have made it a bit lower, thus causing my cardiac symptoms to worsen.
    I don’t know what to do, and I am worried I have really messed up my progress.

  2. It’s good to hear from a physician experienced in treating patients with high B1. The rest of these comments … rubbish.

  3. Did you take any other supplements along with the thiamine HCL? I keep wanting to try thiamine supplements but when I start reading I get overwhelmed because if you take thiamine you need magnesium, if you take mag you need calcium, if you take calcium you need D3. If you take D3 you need K2 and I’m so overwhelmed I don’t know where to start.

    Past few days I’ve been taking thiamine HCL 200mg a day and not feeling great but then last night I took a mag/calc/D3 supplement along with it and today I feel more crazy and agitated and worse than ever. I’m so lost and I’m wondering if there’s a step by step plan or process written out somewhere for someone like me to follow and stick to.

    • Take magnesium glycine alone for a week or two before taking thiamine. Don’t take calcium supplements or Vit D at all. You wont need those once you have adequate magnesium anyway. Magnesium is the limiting factor. When magnesium is taken with food then you will absorb more calcium in your diet. You will also metabolize more vit d that you already have in your body. Calcium, vitamin D and thiamine all compete with each other for the magnesium you take.

      • I tried a lot of different magnesiums and they all made me suicidally depressed and anhedonic. It was horrific. No way I could do two weeks of that. Glycine is the worst.

        • Just wondering if you have tried Remag. It’s a liquid magnesium. If I take any more than 100mg of magnesium glycinate I get anxiety.

        • I had the same. None of the magnesium forms would work. I assumed it was because it hits the stomach acid. So I tried liposomal magnesium (capsules). Works wonders. The only way to circumvent the digestive system and get magnesium in my body.

  4. If one experiences a paradoxical reaction to thiamine, would you say this is a sure indicator that they are in fact deficient? Thanks.

    • It seems to be. Something to do with either electrolytes rebalancing themselves in the cells (thiamine deficient population has 20-30% less potassium in the cells, and higher levels of sodium) or a build-up of other nutrients that are suddenly being utilized (B12/B6/Folate all seem like potential offenders here, since our downregulated processes aren’t fully utilizing them without the thiamine. So when you finally get a large dose, at least in my case, it was like being hit with a truck. Huge amounts of energy, talking 10x as fast, etc.) This probably varies between person to person, and it could be some combination of these things (electrolytes definitely coming into play when it comes to mitigating the reaction,) but as Dr. Lonsdale has pointed out before, it’s impossible to know for certain because it hasn’t been studied in depth. All theoretical.

      So to answer your question: Based on the theory, yes if you suffer a paradoxical reaction from normal B1 or Benfotiamine (not TTFD though, as that stimulates anybody,) then it should indicate deficiency. However, if all you see is improvement in symptoms, you are still likely deficient. And if you see no effect at all, you should be of sufficient status unless maybe you didn’t have enough other B vitamins (b12, folate, etc) to activate and utilize the B1. Again, this is all theoretical.

      You should, however, make sure you’re not deficient in other Bs, or that you don’t have reason to be, if you experience a paradoxical reaction. It seems like it might be possible to have negative effects from high dose B1 if your B12, Folate, or other B statuses were in question. Most of those seem easier to identify though, based on blood tests.

  5. Are you taking Magnesium?
    I don’t get those reactions to high dose Thiamine because I take Magnesium. There’s a BIG difference between taking high dose Thiamine with and without magnesium. The panic attacks and all that doesn’t happen when I take Magnesium.
    I take Magnesium Glycinate Chelate. It’s easy on the digestive system and highly absorbed.

      • Since they work in tandem, this is a good indicator you need them and your system is rebooting. Like the author said, it sucks when you start out but it’s worth he grind. I often recommend people start with magnesium first if they haven’t supplemented with it before since most of us are deficient in it too. Taurate, malate, and threonate seem to work best and it may be better to stay away from glycinate if you get agitated or anxious. Once you can take 400mg/day of magnesium without much in the way side effects, start low and slow with thiamine in addition to a good B Complex. If you want extra help then get thiassist from objective nutrients (it’s worth it) but I’d hold off on D and K and try to get it from the Sun and a healthy diet of animal foods which everyone should be doing regardless. Good luck! You got this!

        • Tried malate. Caused suicidal depression and severe anhedonia like the rest of the magnesiums I tried. I don’t think that’s a good indicator at all. I’ll just take my thiamine HCL without magnesium.

  6. Hello. I have one question – what would you say is the upper limit daily dose for B1 vitamin? Every time I go higher with my dose (by 50mg per week) I have a reaction that tells me I need even more (anxiety, irritability, burning eyes, nightmares). Currently I am on a 400mg per day. Can I make the dose even higher?

  7. Hi
    I am not sure whether I have hit the paradox or too high a dose.
    Brief history
    2019 – unexplained, excessive periods of fatigue
    Dec 2020 – I was bedridden unable to,lift my head off the pillow with cfs, and pots(neuropathic) suspected cause Elhers Danlos Syndrome. And then vestibular migraines.
    April 2020- I started 300mg b1 hcl and titrated up every few days to 600mg. Following an article on Health rising ( and in consultation with my doctor. No significant or sustained improvement noticed in the short term.
    I also cleaned up my diet – hi protein, low/good carb, vegetarian, home made, no packaged stuff.
    I also added b12, b complex, vit d, c, magnesium and calcium
    Then my doctor introduced medication. I continued on 600mg thiamine but paused dose increases.
    Present day
    April 2022 – A year later I am much improved, upright much of the day and taking short walks outside but still a long way to go.
    My medication is stable (florinef, midodrine and Dextroamphetamine) and my health improves each week.
    I was keen to complete my b1 endeavors. So continued titrating up .
    21 April 2022 increase to 700mg
    24 April 2022 increase to 800 mg
    29 April 2022 increase to 900 mg
    Feeling good, more and more energy.
    2 May 2022 feeling a bit tired but within the realms of normal
    3 May (today) – feeling awful, awful sleep, dizzy, woke up anxious, tired from the get go, unsteady on my feet. Spent most of the day with my eyes closed on the couch. Just don’t feel like myself at all. Where as for the last few weeks I went for a 20 min walk and did 30 mins Pilates each day.
    Have I hit the paradox or is my dose now too high?
    Did taking 600 mg all that time help? Have I already been through my paradox last year. Is b1 only beneficial at your highest tolerated dose? In Constantine’s research they had people of my weigh on 1110 mg per day.
    Your advice is greatly appreciated.
    Kind regards

    • You’re probably just pushing yourself too much. Expecting constant improvement. Very typical for us ME/CFS patients. Everyone — even very healthy people — shouldn’t exercise every single day.

  8. Jeff wrote <>

    This is a common experience with many supplements, especially those which deal with energy or neurotransmitter production.

    When the body is in a nutrient deficient state, biochemical reactions are in a hung state, waiting for a specific nutrient to come along. When that nutrient finally does arrive (thiamine in this case) these hung biochemical reactions proceed to go to the next step and can proceed rather quickly. In your case, I would suspect the electron transport chain in every cell in your body was just waiting for thiamine to show up. When thiamine did arrive, energy production went into high gear. It’s like turning the power on all at once. That could easily explain your initial symptoms.

    Another example of a problematic hung biochemical pathway is when someone is severely dopamine deficient. Tyrosine, B6, and zinc are often recommended in these cases. But, taking these three supplements together will likely cause dopamine production to rapidly go into high gear, perhaps sending the person to the emergency room with tachycardia, high blood pressure, and aberrant thought patterns. This will invariably lead to a panic attack. The panic attack will engage the amygdala, and cause the newly produced dopamine to be converted to norepinephrine and adrenaline, worsening the situation.

    • I think the initial symptoms are due to energy metabolism doing worse, experiencing pseudohypoxia, low energy metabolism at cellular level and reduced ATP inhibit proper functioning of Na/K channel and hence higher efflux of K ions. The panic may be due to Methylation process going heywire trying to adjust to the demand placed on it.

    • Seems likely. I imagine this is similar to having large stores of other Bs built up from something like a high dose B6/B12/Folate on their own. Suddenly you get B1, and you just go into overdrive (my personal paradoxical reaction… infinite energy to the point where i’m unsteady and jittery, and can’t talk slower than 10x speed.)

      I had a fairly high B12/Folate status when I tested, searching out my issues a while back. And I suspect that plays a role. I suspect this is also why many people tolerate certain vitamins or complexes for X amount of time, until suddenly they start feeling … icky after taking them (or having outright histamine releases / palpitations.)

  9. Because you were all raised on pharmaceuticals, you expect immediate response from thiamine and other vitamins. This is a completely new treatment and a handful of physicians are using it. Check or for a physician

  10. Unfortunately, thiamine treatment is brand new and used by a mere “handful’ of physicians. The probably best approach is to start treatment with 5-10 mg, wait until paradox subsides and then begin to increase the dose slowly, trying to find the “ideal” dose. If symptoms improve with escalation, but then begin to return, you have probably exceeded the “ideal” dose, so reduce it. You are trying to flirt with Yin and Yang, the ideal balance that applies to everything.

    • It may be a niacin deficiency. Please do not underestimate the requirement of other B vitamins. You may be deficient in others too. Plus the nutrient interactions are so complex that you cannot choose to leave anything. For eg you need folate to activate thiamine to TPP. High amounts of thiamine makes you require more riboflavin as you excrete them more. Then high energy demand needs b6 as well for transamination, transsulfuration reactions. as you are excreting more riboflavin, you may not activate b6 well. B6 is needed to stimulate tryptophan to make more niacin. You may have poor biotin absorbtion or activation, which indirectly effects transport proteins of thiamine. You need good methylation status anyways.

      • B6 is more likely the problem. Google B-6 toxicity and you’ll come up with dozens of sites with thousands who have developed neuropathy etc…

  11. Jeff, I was thinking about your blurry vision comment. I just thought I’d mention this in case it resonates with you. I discovered that I am one of those rare people for whom Niacin B3 affects my vision. You mentioned taking a B-complex and I cannot take a B-Complex because I’ve never found one without niacin and even a little bit bothers my vision (all versions, even NMN and NR, although for some reason I can sometimes handle NMN for several days or so before the vision gets blurry) So I have to take my B-complex components separately. It’s a bummer because obviously B3 is an important nutrient.

  12. I’m hoping that by posting my question, somebody with a similar experience would be able to provide some insight into what is happening with my body. I started taking Allithiamine (TTFD) a couple of weeks ago and experienced clarity of mind and other improvements. However, I began to bloat with symptoms of hyperacidity. I began to cough up stomach acid and my throat was burning. Now, i burp up smell of Allithiamine shortly after i take it. Is this considered paradox reaction? If not, what should I be doing to fix this issue?

  13. Thank you for posting this. I’m only on day 3 of thiamine hcl 50 mgs and apparently that was too high for me. I ended up with a violent migraine and racing heart along with a slew of other symptoms. I tend to be very sensitive so this isn’t a huge surprise but I was expecting to feel better not a million times worse. I also suffer from cbs mutation so anything sulphur related causes issues. I was floxed multiple times and have a rather long nightmare story as most with autoimmune immune and urinary issues do. These days I’m sure many women since were prone to uti have been on a host of quinolones and other drugs known to block thiamine, folate and others. I was being drugged at such a young age I have to wonder if I would have been healthy otherwise. I’ve been in a battle since I was a young girl. Now in my 40s and still fighting but losing a lot of my ability to do so especially when so much of what is supposed to make me feel better is counter indicated because of some of my mutations or because I just can’t seem to tolerate it. Stories like this are imperative for so many of us who are fighting this mostly on our own. It’s hard to know what’s normal and just a paradox reaction, a homeopathic proving or a herx or just something we shouldn’t be taking. The testimony of others is very helpful in what seems like a constant guessing game for many of us.

    • This is so well said.

      I’m also having sulfur reactions to thiamine mononitrate, 300mg. It seems to have cleared my brain fog but made me feel that…sulfur poisoned feeling. CBS mutations over here, too.

      Did you end up continuing? What was your experience? Thanks!

      • What is sulfur poisoning feeling? What are the symptoms? What are we supposed to take instead? I have been getting benefit from mononitrate but I paradox bad so can’t get above 1.5 mg.

      • You need the trace mineral molybdenum to process any sulfur compounds. A deficiency could be causing the reactions.

  14. Hi Jeff,

    Thanks for your story. I am going through the same symptoms. I will start thiamine HCL this week. How bad is your tachycardia in terms of BPM? Also, did you have any mild headaches from time to time? I went through many medical examinations and all the docs told me that I am physically fine and that my tachycardia is caused by stress. I know that is not the case since everything started with an antibiotic just like in your case.

  15. Thank you for posting this information. It’s encouraging to hear this. Can I ask what you are adding for b12? What type are you taking? Is it tablet? Liquid or injections? I feel that this might help me along.

  16. Thank you so much for writing this. I’m sooo glad you are improving!! I’m in this fight now going in 5 weeks. I finally had to stop ttfd after 4 weeks of trying various doses and methods.
    I am in hcl and tolerating and slowly increasing . Mixing in water sipping through the whole day helps. I hope you update again:)

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Previous Story

Share Your Hysterectomy Experience

Next Story

Miracle Maker Ollie: How a Plastic Scooter Outperformed Modern Medicine

Latest from Case Stories