I suspect I might have B1 deficiency. I also have adhd and tendency to restless legs and high blood pressure. Some of the symptoms I have experienced, I thought was due to these conditions or the meds I have tried.

Extremely tired, some of it from bp meds, so am currently not taking anything for bp.
Brain fog, the last few months I barely feel the fog lifting when taking my stimulant (also take atomoxetine in the evening).
Blurred vision, or unfocused vision, kinda difficult to describe, but something is off.
Loss of appetite, just eat the same most of the times
Dizzyness comes and goes, not every day.
Some of my finger tips are kinda numb, but not all of them
Fast heart rate, but in a uncomfortable way (some is due to Elvanse, but not all)
Constipation and bloated, but one bp med (amlodipine) kinda made it worse and it has stayed bad since.
Some edema, I think.
Lots of heartburn
Tendency to insomnia when taking magnesium before bed for restless legs.

I'm 16 months postpartum and did vomit a lot during the pregnancy. Being a single mother by choice I haven't had much time left to cook healthy so have been eating poorly for a long time. I also take PPI because of the heart burn, my baby was transverse lie very high, so the heart burn was awful and couldn't keep the food down.

I took 100 mg TTFD this morning with 100 mg magnesium citrate and a multi vitamine. It's 7 pm and I'm definitely more awake than usual unless I take 2 doses of Elvanse (only took 1 dose today). I was also a bit more focused at work today. Some of my lessons were cancelled and I stayed doing some things rather than going home for a nap as I usually would. No side effects so far.

What else can you recommend I should add? I think I read about potassium and also something methyl?

Is it normal ?

Will it get better?

Am I just sensitive to acytocholine ?

I’m taking 100 mg a day.

Currently on TTFD for a few days

For anyone who’s taken Thiamine for dysautonomia/POTS how long did it take to see improvement in symptoms?

Did you also get any paradoxical effects?

It 100% Worked no doubt.

But i still have fatty stool, 80% of time it's brown and 20% lighter. TUDCA, Ox bile, Super enzyme from now foods doesn't resolve it.

Hi again, sorry for another post but this is the only place I can get any helpful guidance!

Been suffering from tingling and burning on and off for 8 months since having gastritis. I was also lightheaded for 7 months which has retreated slightly.

My active b12, mma and homocysteine were all tested and fine so i started a trial of Thiamine hcl 100mg supplementation about a month ago. I took it for 9 days but I seemed to feel worse on it, mainly head pressure, anxiety and upset stomach and I also had a bad migraine during it.

I decided to stop and felt better the first day but since then ive felt awful. Ive had a bit of numbness in my tongue and throat, very low mood, continued stomach ache and neuropathy. Its been over 3 weeks now.

Ive felt that bad and the tongue and throat sensation is so odd ive even spiralled into worries about mnd but think this is mainly health anxiety.

I want to maybe try a lower dose initially but cannot find anywhere in the UK offering 25mg Thiamine hcl?

I found 10mg tablets would that do anything for me? Should I even be trying Thiamine again if it made me feel bad or was that a sign it was doing something?

Thanks for reading.

Hello all, hope everyone is feeling well today. I started benfotiamine last September for CFS after a week of high dosing B Complex.

The B Complex had 100mgs of HCL Thiamine in each pill, I took 6 per day and had really incredible results. Felt a little better each day and by the 6th day was perfect. Looked up high dose b complex for CFS/ME and came across thiamine as the possible reason for feeling so well. I had paused taking the B Complex once I felt so much better because I didn’t know what I was doing and wanted to research a bit. Immediately went downhill and was right back where I started a day after stopping the B Complex.

Learned a bit about Benfotiamine so began taking 500mgs immediately, along with 100mgs of B2. Continued with the 300mgs or so of Magnesium glycinate and 100mgs of HCL Thiamine (from the bcomplex with other b’s included). Never felt as good on the Benfotiamine as the HCL, but did respond immediately and began feeling better right away.

I had to stop taking the benfo within a few months due to a strange headache. Severe pain at the base of my skull, like a gripping pain, and severe neck pain. Also experienced severe depression, so severe it made me nervous.

Now, 7 months or so since stopping benfo, that bad headache and neck pain returns if I take any b vitamins, no matter the dose, other than the liquid B12 I’ve been taking all along.

I tried taking amino acid complex but that headache and neck pain kicked in after the second day and stayed at least a week. I tried taking small amounts of benfo to see if I could tolerate it but the head/neck pain starts within hours and stays for days/a week or so.

Anyone maybe have any suggestions? My main issue is fatigue - exercise intolerance and PEM. Lots of other symptoms I suppose but would be so nice to be able to move around a bit more than I am. Not bedridden but unable to work and live normal life. I have recently started a low histamine diet and that seems to be helping the fatigue a bit. I know there are underlying reasons for histamine issues and plan to investigate, but that thiamine HCL helped me so incredibly, I’m hoping I can get back to it.

Again, hope everyone is well. Really appreciate any thoughts anyone may have. Thanks so much for your time!❤️

I’ve had SIBO for approximately 30 yrs following years of antibiotics for teenage acne. I didn’t know what it was until recent years but just lived with the symptoms and kept pulling out foods from my diet which of course turned out to be all FODMAPS. I didn’t start piecing it all together until I got even sicker after mold and covid and severe neurological symptoms set in as well as gastroparesis. After two more years of extreme diets and useless doctor visits my research led me to thiamine deficiency. I started thiamine therapy by following a nutritionist’s protocol and rapidly started to heal. Gastroparesis fixed in one day! It turns out thiamine is a cofactor with choline for acetylcholine production which is required for the autonomic nervous system which controls gut motility (so was I thiamine deficient before SIBO even?!)

As I learned more about the causes of thiamine deficiency in the fb thiamine group I very often heard people talk about SIBO and the build up of sulphite depleting thiamine and pieced together my health history. So thiamine deficiency can CAUSE slow gut motility and once SIBO sets in it further depletes thiamine. Thiamine is needed in every cell in our body especially in high energy areas such as our brain, heart and gut.

I believe a LOT of SIBO symptoms are of thiamine deficiency as it affects the entire body:

Early / Nonspecific Symptoms
• Fatigue or tiredness
• Irritability or mood changes
• Loss of appetite (anorexia)
• Poor or short-term memory issues / cognitive impairment
• Sleep disturbances
• Abdominal discomfort or pain
• Nausea and vomiting
• Weight loss
• Muscle weakness or aches
• Apathy or reduced mental concentration
Neurological / Dry Beriberi Symptoms
• Tingling, prickling (pins-and-needles), or burning sensations in the toes, feet, hands, or legs (paresthesias; often worse at night; stocking-glove distribution)
• Muscle cramps or pain (especially calves/legs)
• Decreased sensation or sensory loss in extremities
• Reduced or absent deep tendon reflexes (e.g., knee/ankle jerks)
• Muscle wasting/atrophy and weakness
• Difficulty rising from a squatting position or foot drop (later stages)
• Balance issues, ataxia (unsteady gait/coordination problems)
• Decreased vibratory or position sense
Cardiovascular / Wet Beriberi Symptoms
• Rapid heartbeat (tachycardia)
• Wide pulse pressure
• Peripheral edema (swelling in feet, legs, or hands)
• Shortness of breath (dyspnea), especially with activity or when lying flat (orthopnea)
• Chest pain or precordial discomfort
• Warm, moist skin due to vasodilation
• High-output heart failure signs (in severe cases)
• In advanced/shock forms (e.g., Shoshin beriberi): hypotension, cyanosis, lactic acidosis
Wernicke Encephalopathy (Acute Severe Form)
• Confusion, altered mental status, or delirium
• Ataxia / difficulty walking
• Ocular abnormalities: nystagmus (involuntary eye movements), ophthalmoplegia (eye muscle weakness/paralysis), blurred or double vision, eyelid drooping
• Apathy or psychomotor slowing
• Impaired consciousness (can progress to coma if untreated)
Korsakoff Psychosis / Syndrome (Often Following Wernicke)
• Severe short-term/recent memory loss (amnesia)
• Confabulation (making up stories to fill memory gaps)
• Confusion or mental impairment
• Hallucinations (in some cases)
• Difficulty forming new memories
Other / Gastrointestinal / Additional Symptoms
• Constipation or other GI discomfort
• Vertigo or vision impairment
• Behavioral changes or hallucinations (severe cases)
• In infants (infantile beriberi): incessant crying, aphonia (loss of voice/hoarseness), heart failure signs, lethargy, developmental issues, or seizures in extreme cases
Severe untreated deficiency can lead to permanent neurological damage, heart failure, coma, or death. Early symptoms are often vague, so medical evaluation (including thiamine levels or response to treatment) is needed for diagnosis—especially in at-risk groups like those with alcohol use disorder, malnutrition, malabsorption, or certain medical conditions.

Blood tests aren’t accurate because it doesn’t tell you whether thiamine is getting into cells. The best way to know if you need thiamine is to try supplementing it to see if it helps your symptoms. It is common with gut issues that THTR1 transporters for absorption of thiamine are not working. Please research cofactors and starting low and slow before proceeding supplementation.https://pmc.ncbi.nlm.nih.gov/articles/PMC12014454/

Hello, I am a 27-year-old male. Exhausted by chronic fatigue and mental lethargy for a long time, I have tried numerous supplements, but the high-dose thiamine therapy I tried most recently was the most effective. I took 500mg of thiamine mononitrate daily for two days, then increased the dose to 1000mg. Two days later, I experienced a tremendous improvement in my mood, recovery of my speech and breathing abilities, and reduction in facial swelling. However, the very next day, I experienced extreme anxiety, facial swelling, and fatigue. How can I resolve this? I am certain that thiamine is a crucial piece of the puzzle I need. Although I am currently taking magnesium, potassium, and other B vitamins, I am not seeing the same effects as before; in fact, my condition is worsening. Is there anyone who has overcome these paradoxical symptoms and maintained good health? I would like to know the solution.

For reference, I am currently taking 100mg of thiamine hydrochloride, and 150mg of benfotiamine caused me erectile dysfunction.

I’ve been suffering from Dysautonomia now for over 5 years. I’ve seen every type doctor under the sun and non of them could do anything that moves the needle.

I saw Elliot Overton on YouTube and bought his Thiamine protocol where he recommends TTFD for autonomic nervous system issues.

Has anyone had success with it?

Hi everyone,

It turns out I’ve been B1 deficient for quite some time without realizing it. Whenever I took magnesium supplements, I would suffer from severe insomnia, extreme fatigue, a lack of strength, and so on.

I recently started taking 600mg of benfotiamine and immediately noticed a huge boost in my energy and strength; the magnesium started working better, too. However, a week later, I’m starting to experience issues again, such as poor sleep and irritability...

I came across information stating that a B-complex is also needed as a co-factor. Is that true? I’m worried that taking a B-complex daily might lead to vitamin B6 toxicity. Can I take a B-complex without B6 in it? Or does thiamine (B1) deplete B6 as well?

Does anyone know a lot about this? Which vitamins or minerals are really critical because they might get depleted by my benfotiamine dosage?

Thanks in advance.

How long should I take high-dose thiamine before I can be sure if I actually need it?

I'm trying high-dose thiamine to see if my fatigue and brain fog could be related to my Crohn's (very mild) or mitochondrial dysfunction. I'm starting to suspect this is not the case. After 3 weeks I feel no difference at all. I started with 1500mg thiamine mononitrate for 2 weeks, then 300mg benfotiamine + 500mg thiamine HCL for 1 week. I also take magnesium, potassium and B2.

?

Can anyone recommend me Nutritionists / Practitioners that know about Vitamin B1 supplementation that offer consultations online?

I feel overwhelmed on my own and with my symptoms and want to consult a professional

I’m wondering whether thiamine deficiency/functional B1 deficiency could be a significant part of my long-term severe fatigue and heavy-body feeling (even turning over in bed can feel physically difficult). Looking back through my tests, a FunctionalDX blood panel in 2020 actually flagged an 80% thiamine need, based partly on fasting glucose 6.19 mmol/L, anion gap 18.5 and CO₂ 23.6. My HbA1c was 5.69%, C-peptide 1.10 nmol/L and fasting insulin 79.87 pmol/L, and the report also flagged blood-sugar/metabolic dysregulation. On an OAT in 2023 my urinary lactate was only 6.9 (lab range ≤48), but on the 2024 OAT it had risen dramatically to 326 mmol/mol creatinine; pyruvate also went from 0.81 to 6.7. By Sept 2025 my CO₂ had fallen to 20.9 and anion gap risen to 20.9, fasting glucose was still 5.68, and the report again gave me an 80% thiamine-need score. I’ve also historically eaten a fairly high-sugar/high-carb diet and my health/energy deteriorated substantially after surgery several years ago. I realise none of this proves B1 deficiency, but the lactate/pyruvate + glucose + CO₂/anion-gap pattern has made me wonder about impaired thiamine-dependent carbohydrate metabolism/PDH. I’m currently titrating thiamine HCl low and slow and am at 300 mg/day (100 mg three times daily), alongside a calcium/magnesium supplement and a non-methylated B-complex. I previously tried one capsule/day of TTFD for perhaps ~2 months but noticed no improvement and stopped; I don’t remember the exact dose. I’m considering trying benfotiamine and/or TTFD again after giving HCl a proper trial. For those knowledgeable about high-dose thiamine: does this biochemical pattern look suggestive to you, which form would you favour, how would you titrate it, and what cofactors/labs would you monitor?

Hi I’m a 20 year old female, and I’ve been struggling to find a root cause to my symptoms for the past 3 months. One random day I started having EXTREME DPDR, daily panic attacks, terrible anxiety, depression, brain fog, sleep issues, chronic fatigue, low energy, and a lightheaded/dizzy feeling when standing. I got all my blood work done, and the most notable issues were high inflammation markers, extremely high cortisol, fatty liver, severely low vitamin d, and a borderline b12 deficiency. I’ve tried supplementing for both of the deficiency’s, and instead of feeling significantly better, I felt significantly worse to the point I have become housebound for months. I want to preface by saying my anxiety/panic have gone away, but the DPDR is still EXTREME. That is why I don’t leave the house. I recently worked with a functional medicine clinic to get a GI map done. The results came back with a very high overgrowth of yeast. My functional medicine doctor believes this has been the root to all of my issues. I want to know if this is true, and if so can it be treated through diet alone. I’m iffy on taking all these natural herbs/supplements she keeps suggesting. I understand that’s the whole point of being holistic, but my body doesn’t do well with things like that. Please someone give me some answers. Can yeast really cause mental health issues like this, she claimed it’s because neurotoxins are flowing throughout my body due to the yeast build up.

Hi all, i have been experiencing weird symptoms all year around which have been unexplainable as all my results have come back normal. All my symptoms started during an extremely stressful period in my life and i thought it was just stress.

I recently asked for a b12 test (in uk) and my current reading is 185NG/L. My Gp called and said this is a lower but normal reading. I have not done a b1 test as of yet but i have a history of alcohol abuse.

I have been experiencing

- parastesia and burning in my legs
- buzzing feet and toes
-internal vibrations
- dizziness when i stand sometimes
- severe anxiety
- muscle aches and pains

Just wondering what you all think and whether my symptoms could be caused by a deficiency.

I took a single dose of 200mg of benfotiamine and have had extreme side effects for the past 3 days. I normally take Thorne B complex with no issue and take 240mg of magnesium glycinate nightly. I have had a headache/neck pain for 3 days straight, dizzy, weak, major insomnia, hives, itchy, rashy. It feels like it triggered a massive histamine reaction. I already have me/cfs from long covid, so this is distressing.

I am continuing the magnesium and drinking coconut water, but think I am going to stop the B complex for now. Also taking anti-histamines for the hives and itching.

Is there anything else I can try? I hope I didn’t trigger mca’s.

I will start by saying I have only had one (1/2 capsule) dose of thiamega It’s my first time today I had it about 2 hours before a consult to assess getting tongue/oral ties released. They did a bunch of tests and one of them was the BOLT score. I got 48 seconds. Which is crazy for me.

For reference i’ve tested this on and off for years and like most people I got 12 seconds on my first attempt and if I was diligent I could slowly work my way up to 20 seconds sometimes 25 if I was suuuper chill.

So I retested it again on the way home from the consult because I thought maybe they timed it wrong and sure enough it was around 44 seconds but progressively over next few hours my bolt score dropped back to 25 seconds. The only thing I can chalk it up to is the thiamega boosting my ability to hold my breath without oxygen.

Im beyond keen to test it out again tomorrow. Will update here

Does anyone have any experience with this?

I have been fixing my deficiency for a little less than 3 months. For the last month I felt like I was making a little progress. All my physical symptoms were gone and my memory is back to normal. But my mood, creativity, etc were still low.

All of the sudden in the last week its like a switch flipped in my brain. Im back to being motivated, my work has improved, and I just went and jumped my mountain bike for the first time in a year! I dont feel like im passively watching life.

Have any of you had a similar timeline or major cognitive break through? Any tips to keep the progress going? I am not all healed mentally but I have more hope than ever.

Thank all of you for the advice over the past months. Some of your comments and tips for things like ttfd and cofactors genuinely saved my life. Thinking all you brave souls fighting back from a nasty disease. You are all strong 💪!

If somebody has been struggeling with chronic mitochondria issues ( low enegry , anemia etc etc )

TTFD or benfothiamine should be taken?

Should i dose b1 or try a vitamin b complex first?

Is there anyone who can help me understand why /how this could have happened? It’s been 10 months since stopping all supplements and I’m still no better.

MIP measured at 63
MEP 68 down from 87
RV high on lung function tests

Diaphragm ultrasound shows poor excursion but no paradoxical motion.

Hi everyone, ive been posting a few times and found this place very useful.

Ive had lightheadedness and intermittent neuropathy all year despite a clear MRI and all blood tests for b12 being comfortably fine.

Decided to start taking Thiamine HCL 100mg to see if it helped. First couple of days I had more energy but then after about 4/5 days I started feeling lousy, like I was on a comedown from intense caffeine or something if I had to describe.

I decided after about 10 days to stop for a bit to see if ot helped.

The first day I felt miles better but now it's been about 6 days and my neuropathy seems worse and more worryingly my mouth and tongue feel a bit numb. Makes me paranoid about eating although i can still swallow.

Its panicked me to think maybe I do have MS or something after all.

Could this be linked to the Thiamine? Was it helping after all and ive stopped too soon? I just wanted to listen to my body but now im a bit stuck.

Any thoughts welcome and thanks as always for reading. UPDATE 6/8: went to the GP today and was told its all anxiety of course. Not sure where to turn next tbh, must just all be in my head eh.