Metronidazole toxicity and doctor denial

Metronidazole Toxicity and Doctor Denial

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Harsh Revelations

“It’s time for you to get past this and move on with your life.” As I sat on a cobalt blue exam table, my primary care physician’s words ping-ponged throughout my mind. Even then, I knew it was a pivotal moment, one that would steer my life into a new and terrifying direction no patient wished to venture.

It was the moment I lost all faith in conventional medicine.

August 12th, 2015.  In front of me, my doctor (we’ll call her Dr. Perry) stared quietly, waiting for a response. There was no anger in her eyes, more like desperation. She was desperate to “reach me,” to get me to understand—what I had was depression and an anxiety disorder. These symptoms I’d described repeatedly, a page-long manifesto of misery, weren’t real—they couldn’t be. It had been two months since I took the antibiotic, metronidazole (Flagyl), and there was no way the medication could be affecting me now.

What she didn’t realize was…I wasn’t the one in denial.

She was.

“I have come across many instances of this kind of reaction by physicians,” explained Derrick Lonsdale, MD, and author of Thiamine Deficiency Disease, Dysautonomia, and High Calorie Malnutrition. “The many symptoms expressed by the patient are interpreted as ‘psychological’ because they appear to be bizarre and conventional lab studies are often normal. The diagnosis is little more than an accusation of malingering. Furthermore, the absolute denial of any sort of vitamin deficiency causing disease in America has become a virtual mantra throughout the medical profession. Any suggestion of this by the patient reinforces the physician’s diagnosis of neurosis.”

“It is very bizarre,” he continued, “to see repeated stories where a drug reaction is denied by physicians. Worse yet is the doctor’s accusation of a patient’s imagination as the cause of symptoms. The Physicians Desk Reference often has one or even two pages listing the toxic effects of a given drug.”

The Beginning of my Metronidazole Nightmare

In June of 2015, I had a gut infection called c diff.  Dr. Perry had diagnosed it and prescribed metronidazole, but five days into treatment, I found myself in the ER, unable to walk or speak.  Included with those symptoms was a list of other issues so random, it was as if someone was picking them out of a big Bingo ball cage: dizziness, difficulty concentrating, shortness of breath, hand tremors, fatigue, brain fog, weakness.

At the time, I wasn’t afraid, because I believed this problem had an simple solution: just stop taking the drug and—poof!—all symptoms would disappear like a quarter in a magic trick.  Another antibiotic was available for c diff, vancomycin, and the problem-solver in me thought this was a no-brainer.

In the ER, they did a CT scan, an EKG, took a urine sample and multiple tubes of blood, only to conclude that the issue was low potassium, even though not all my symptoms matched that diagnosis. Trusting the doctors, I allowed them to discharge me. I got a prescription strength potassium supplement, and then took another dose of metronidazole before heading to bed and then more the following day.

Less than 36 hours later, my mother rushed me to Dr. Perry’s office, as I once again lost the ability to walk and speak.

From the clinic’s lobby, my mother had to half-drag me into the exam room. When she spoke the words “metronidazole” and “side effects” to Dr. Perry, they were met with a face full of skepticism.

“I’ve never seen Flagyl do that before,” Dr. Perry insisted.

After arguing with my mother, the doctor did admit me to the hospital for observation. Maybe Dr. Perry and the ER doctors weren’t well-versed in adverse drug reactions, but hospital physicians were certainly in-the-know.  Right?

Naïve Patient + Ignorant Doctors = Poor Prognosis

“I just can’t imagine it’s the metronidazole,” the pharmacist explained.

Six hours into my hospital stay, two doctors stood by my bed, the pharmacist sandwiched between them. My symptoms had once again improved, and my mother and I had explained what had happened like a song set on repeat. The doctors had tried—and failed—to convince us that metronidazole wasn’t the problem.  So now they had brought in the big guns: the hospital pharmacist. We argued with her—every symptom I had was listed as a side effect of the drug.

“But that type of reaction…it would be really rare,” she had explained.

Game over. Not one doctor believed metronidazole was the problem. They had no other explanation, as my potassium levels had returned to normal now. How could having this drug reaction be so painfully obvious to me and my family, but so confusing to every medical expert I saw?

If left untreated, my infection could be fatal. Unsure what to do, I said softly, “I have to take something to treat the c diff.”

Half an hour later, the nurse brought me more metronidazole. I took it. Later that evening, I took another dose. Then the all-consuming panic set in.

The “Hysterical” Patient

That night in the hospital, my heart pounded so hard, I was afraid it would burst out of my chest “Alien” style. My face felt searing hot while my body shivered.  The anxiety was set to PANIC and stuck there. Adrenaline rushed through my veins like it was fixed to a 30-second timer.

Nothing felt right.

I didn’t fall asleep until 4:00 a.m., and less than two hours later, I woke with a startle although there was nothing there to surprise me. Again, my physical symptoms—the difficulty walking and talking—had come roaring back, along with brain fog, hand tremors, dizziness—the works.

I had an orderly help me to the bathroom and there, I burst into tears. I cursed through slurred words and short breaths, and cried from sheer terror. C diff was a gun to my head, metronidazole a poisoned apple in my hand. And I was being forced to choose between the two.  Another antibiotic was available to treat my infection, but the doctors refused to give it to me.

They were so certain my symptoms were just in my head, they were willing to bet my life on it.

Late morning, my symptoms partially subsided again, and my father visited; he argued with the doctor, my father’s voice much deeper and menacing than Mom’s and mine. “I don’t understand what the big problem is here. She wants to change her meds—so why can’t you do that?”

The doctor in charge of my case finally agreed to give me a prescription for vancomycin, but only after I left the hospital and only if my symptoms were still “bothering” me, as he explained.  Later, after my father left, the same doctor entered my room unattended. He approached my bedside, shoulders squared. “I’m wondering—do you have trouble sleeping at night?” he asked.

Unsure how to answer, I replied sometimes, yes, when there were a lot of things going on.

He bobbed his head up and down, this all-knowing look on his face. “I think you need to see a psychiatrist.”

The bottom fell out of my stomach. I sat there, slack-jawed.

“It’s just…” the doctor stepped forward, and his professional demeanor caved. Those eyebrows knitted together. Impatience, irritation shone like searchlights from both eyes. “What are you so anxious for?

I didn’t respond—didn’t know how to respond. What was I so anxious for? How could this be a question?

Despite the encounter, the hospital doctors later decided to just go ahead and give me vancomycin, with the off-handed disclaimer, “We still don’t think it’s the metronidazole, but…”

I left the hospital the next day, vancomycin in hand.  Despite this nightmare experience, I was relieved in the fact that things would turn back to normal now. I could catalogue all of this into past-tense.

I was wrong.

“Although in many instances of drug use,” explained Dr. Lonsdale, “the side effects disappear when the drug is discontinued; metronidazole is an exception. Through its destruction of thiamine, it leaves in its wake a severe loss of efficiency in cellular energy metabolism. Unless thiamine is restored, the so-called side effects will continue indefinitely. The disaster comes about because the physician’s failure to take the patient’s symptoms seriously does not lead to effective treatment.”

But You Should be Fine Now…

Things barely improved after stopping the metronidazole. Although a few symptoms resolved, like slurred speech, others cropped up from nowhere—some starting days to weeks after stopping the drug:

  • Difficulty swallowing
  • Frequent urination
  • Constipation
  • Asthma-like respiratory issues
  • Complete loss of appetite (twenty pound weight loss)
  • Inability to stand up straight
  • Difficulty walking
  • Shortness of breath when talking
  • Chest pressure
  • Heart palpitations
  • Face flushing
  • Dry mouth
  • Cough
  • Headache
  • Pressure at the back of the head
  • Neck pain and stiffness
  • Constant adrenaline rushes
  • Anxiety
  • Depression
  • Crying spells
  • Insomnia
  • Extreme fatigue

The list was so long, even I failed to fully understand how all these symptoms were possible in one body.  No medical professional had an explanation for why this was happening and why it didn’t stop after discontinuation of metronidazole.

For two months, I couldn’t care for myself. I stayed with my parents; I lost twenty pounds, and no matter how hard I tried, working full-time was impossible. Before metronidazole, I had three jobs—one as a full-time assistant, another part-time job doing data entry, and one writing freelance articles for local magazines. I had to quit my part-time job, stopped writing, and ended up missing over 130 hours of work at my full-time job over that two-month time span. Despite my symptoms being listed as side effects of metronidazole, no diagnosis was given from any physician.  With no doctor to back me up, at one point I worried I’d lose my full-time job.

In total, I saw eight general practitioners, including my primary care physician, and then a hefty bag of specialists: a cardiologist, an immunologist, an ENT doctor, a psychiatrist, and a therapist (to his credit, the therapist believed I had suffered an adverse drug reaction, but just like me, didn’t know why I still had symptoms). There were tests, from multiple CT scans to X-rays, EKGs, an upper GI, an echocardiogram, a heart monitor, a laryngoscopy, several lung function tests, and about 30 vials of blood taken.

One of the general practitioners tested me for illegal drugs. The doctors had more belief I was a drug addict than the idea that metronidazole could be affecting me six weeks after taking it.

When I was ingesting metronidazole, the physicians either insisted it was incapable of causing my symptoms or a reaction like that was “so rare,” it couldn’t happen to me. Now that I was off the drug, the rhetoric had shifted to: “Well, even if you had a reaction, you should be fine now.”

This not only left me feeling defeated and helpless…but ashamed.  I felt so guilty for being so sick.  It was around this time the suicidal thoughts kicked in.

Out of Body, Out of Mind

Six weeks after taking metronidazole, the insomnia worsened. I went eight days with barely any sleep. I tried every medication a doctor offered to mask symptoms, a conveyer belt of meds: Prozac, Paxil, hydroxyzine, Zofran, Ambien, and then mirtazapine. The mirtazapine allowed me to sleep, and with the rest, my body started to improve and the suicidal thoughts calmed. (It was also at this point I started to supplement magnesium and a general multi-vitamin.)

Now August, two weeks into the mirtazapine treatment, I met with Dr. Perry and that’s when she handed down the diagnosis of depression and an anxiety disorder.  “It’s time for you to get past this and move on with your life,” she told me.

I did something else. I stopped trusting doctors, and began researching metronidazole on my own.

When a Google Search is Better than a Medical Degree

During the first two months after my initial reaction, I had looked into metronidazole but assumed (naïvely) that my doctors were too. They were not. If any answers were out there, it was up to me to find them. So I Googled—a lot. It became an obsession; I learned the history of the drug, where it was created (France), when the FDA approved it (the early 1960s). Whatever clinical trials they did at that time has kept the drug on the market for almost 60 years, despite those trials not being acceptable by today’s standards. The medication was considered “broad-spectrum”—a fancy way of saying it went everywhere in the body. The digestive tract, the bloodstream, saliva, genitals, all vital organs including the heart and lungs. Cerebrospinal fluid.  The brain.

In addition to the trivia-facts, I read countless patient reviews on websites like, and—most of all— People were complaining about the same symptoms, the same motor control issues, heart and breathing problems, and especially the neuropsychiatric issues.  When anyone mentioned visiting their doctor, it was almost always about how the doctor dismissed the patient’s claim that metronidazole was the cause.

Then in late September 2015, I discovered a new term to plug into Google—metronidazole toxicity.  When I did, I found out that what I had, it had a name:

Metronidazole-induced Central Nervous System Toxicity

It was the title of a systematic review, one that collected numerous case studies about metronidazole and its toxic effects on the central nervous system to form statistic data. The example they used in the review was that of an elderly woman. Two days on the drug, she began to have trouble speaking and then difficulty walking, which progressed to her losing the ability to walk altogether. Metronidazole was discontinued and she made a slow but steady recovery.

In total, the symptoms listed on the systematic review were:

  • Dysarthria (slurred speech/difficulty speaking) 66% of cases
  • Ataxia (loss of motor control skills, such as walking) 56%
  • Dysmetria (lack of coordination of movement) 33%
  • Altered mental state (neuropsychiatric issues) 33%
  • Seizures 15%
  • Nystagmus (involuntary eye movement) 8%

And the cause? If you have issues like losing the ability to walk and speak while taking metronidazole, there is about a 93% chance lesions have formed on the back of your brain, specifically the cerebellum. This causes a disorder called “cerebellar dysfunction,” leading to motor control issues, cognitive issues, and a possible altered mental state.

After drug cessation, the lesions disappear 83% of the time over the course of three months.  There is poor correlation between resolution of those lesions and a resolution of symptoms.

Only 65% of patients fully recover from metronidazole toxicity. Another 29% have improvement, but not a full recovery, another 3% have unknown outcomes, and the remaining 3% have permanent cognitive impairment.

Medical Literature isn’t Enough…Really?

Three weeks after finding this review, I showed it to Dr. Perry. I reminded her of my symptoms, especially my difficulty walking and speaking, my slurred speech and gasping to speak.

“I have no documentation of slurred speech,” she replied.

Her words hit me bullet-hard, and I sat there, dumbfounded. She fished through my chart, reviewing my visit to the ER to the hospital—nothing. Not one doctor had written anything down about my difficulty speaking, despite it being one of my most prominent and concerning symptoms.

In fact, none of the symptoms I complained about during my ER and hospital visit were in my records. The only record they had of any significant symptom was from Dr. Perry herself, noting that I couldn’t walk due to “weakness.” I addressed this with her, and she insisted my difficulty walking in June wasn’t neurological in nature.

I sat in the exam room, staring up at the ceiling, allowing the fluorescent lights to sting my eyes.  Could this really be happening?

Despite this new information, Dr. Perry did agree to order an MRI, the only test that could detect those white matter lesions the systematic review talked about. The MRI was performed two weeks later—now it had been over four months since my initial reaction and, sure enough, nothing showed, as the medical literature said was typical by that point.

Any chance of detecting an abnormality was gone.

During this time, I requested a copy of my own medical records and a little over a month later, they arrived. I read them all; the ER visit—the hospital visit. There was nothing, no mention of difficulty walking or speaking, just as Dr. Perry had explained.  But there was one symptom mentioned several times—anxiety. From the ER, my shortness of breath when talking was excused away as anxiety. And from the hospital, my doctors had written it down thirteen times over the course of my forty-eight hour hospital stay.

Then, at the end of the paperwork, was the last appointment with Dr. Perry, and as I saw what she wrote, my hands tightened around the edges of the papers:

“Patient brought an article to clinic today and she thinks she has “metronidazole-induced CNS toxicity” and she wants an MRI.  Of note, the article states patients that have this have cerebellar dysfunction, altered mental status and seizures. Patient has not had any of these symptoms.”

I’ll never know what was going on in Dr. Perry’s head when she wrote that statement. Could she be this much in denial about the drug’s toxicity to permanently mark my medical records like a scarlet letter?  Or was this now her vain attempt to cover her own mistakes? Either way, it boiled down to one truth:

“Keeping accurate records is the sacred duty of any physician,” explained Dr. Lonsdale, “if not solely for consecutive management of the patient, it is surely for the protection of the physician. To leave out major symptoms described by the patient because it does not fit the doctor’s diagnosis amounts to malpractice.”

I Was a Textbook Case of Metronidazole Toxicity

Over the course of several months, my symptoms slowly improved on their own, where I was able to work full-time and live on my own. But flare up’s were common, some bad enough to land me back in bed. I also discovered that the metronidazole’s neurotoxicity is actually listed in the WARNINGS section of its FDA label, noting the key symptoms being dysarthria (difficulty speaking), ataxia (difficulty walking and/or arm control), and dizziness.

I was a textbook case of this drug’s neurotoxicity and none of my doctor’s had made the connection.  Instead, they chalked it up to hysteria.

Excommunicated: MD Edition

Upon all of these new discoveries, I decided to set up another appointment with Dr. Perry to ask her about my medical records, but a week before the appointment, she called me and, as I sat with the phone hot on my face, I listened to her speech:

“Erin, I want you to know that I care greatly for you. I just want what’s best for you. But I don’t think we have the right ‘doctor/patient’ relationship. So I think it is best if, moving forward, I was no longer your primary care physician.”

Later, I found out she not only dismissed me as a patient but had me banned from the large clinic she worked, including another doctor’s office that I’d never visited that happened to be in the same building.

That would not do, not after all that. I got on the phone with her supervisor, who—at first—flat-out refused to meet with me. It took several minutes and a strong declaration, “I am going to have a meeting,” to get her to agree. A month later, I went to the meeting with Dr. Perry’s supervisor and the clinic’s lawyers (Dr. Perry was not present).  Along with me was my mother and a doctor I worked with who also happened to be friends with the supervisor—a lucky break few patients have.

I brought in emails I sent in June of 2015 discussing my symptoms with doctors, colleagues and friends, including losing the ability to walk and slurred speech—that contradicted what was written on my medical records. Along with the emails, I also had a stack of medical literature including case studies, multiple systematic reviews and the FDA label that confirmed metronidazole’s toxicity. My doctor-friend validated my story, my symptoms and research, and I got the more appropriate diagnoses of “cerebellar dysfunction” and “altered mental state.”

Even after getting the diagnosis, no doctor would acknowledge that metronidazole was the cause.

My ban from the clinics was never lifted.

Metronidazole Toxicity: A Not-So “Rare” Problem

Over the course of a year, my body healed enough for me to enjoy social activities again.  Nonetheless, flare up’s would still arise and they could last for days to months with no explanation.

Researching metronidazole more, I discovered the cerebellum wasn’t the only part of the brain affected. The brain stem was the second most-hit region, and the brain stem controls the autonomic nervous system. This includes: breathing, heart rate, blood pressure, digestion, temperature regulation, sleep-and-wake cycle, and your fight-or-flight response, among many others. Metronidazole could also damage nerves throughout the body, including the eyes and ears, a problem many other patients complained about in their reviews.

Branching out online, I connected with other victims of metronidazole toxicity.  I shared the medical literature and created a blog. In addition, I started a Facebook support group; only people suffering from metronidazole toxicity are allowed to join. When the support group began, there were three of us. Now, three years later, there’s over 600 members.

Despite physicians insisting metronidazole toxicity is rare, patients were screaming about adverse effects across the internet. Metronidazole is the most-reviewed antibiotic on, the second-most reviewed on and, on website, metronidazole has the highest number of reviews when compared to all drugs, with the oral version of metronidazole having the 5th highest number of 1-star reviews (when all versions of metronidazole are included—IV, oral and gel—the drug has the highest number of 1-star reviews on the site). In addition, on Askapatient, it had the highest complaints about:

  • Headaches
  • Dizziness
  • Anxiety
  • Panic Attacks
  • Depression
  • Disorientation
  • Fatigue

It also had the second-highest number of complaints about confusion and paranoia.  Patients are clearly being outspoken about metronidazole and its serious adverse effects.  But from the medical community…barely a whisper.

How could this be?

Mechanisms of Toxicity and the Thiamine Connection

In November 2017, I suffered one of the worst flare up’s since my drug reaction in 2015.  It just so happened, during that time, I ran across Dr. Lonsdale’s textbook, “Thiamine Deficiency Disease, Dysautonomia, and High Calorie Malnutrition.” It caught my eye because I recalled the word “thiamine” mentioned in a couple of the articles for metronidazole.

I read the book and every symptom I’d had was listed. Going back to research, I discovered that metronidazole is similar to a ring of thiamine (vitamin B1) and, when it comes into contact with the vitamin, it binds to it, destroying it. This plummets the victim into a sudden, severe thiamine deficiency.

The symptoms of metronidazole toxicity and thiamine deficiency disease are identical.

That was why the drug’s toxicity kept “flaring up.” I had been skating on the edge of this drug-induced thiamine deficiency and any time my body endured stress, it depleted the limited thiamine I had gained and plummeted me back into deficiency.

Within two months of supplementing magnesium and high doses of Allithiamine (a fat soluble version of thiamine), my lingering metronidazole toxicity symptoms either resolved or became so mild, they could no longer debilitate me no matter what physical or mental stress my body endured.

A few months ago, I finished painting a house.

Nonetheless, I didn’t get off Scot-free. It has been almost two years since starting the thiamine regimen and, through trial-and-error, it has become apparent that the damage metronidazole has done is most likely permanent. Enzymes that are vitally important in energy metabolism require thiamine and if the symptoms arising from its deficiency are not corrected early in its manifestations—the enzymes deteriorate due to lack of use. To resuscitate the enzymes, megadoses of thiamine are required, usually for a long time. Symptomatic recovery can be expected unless permanent cellular damage has developed.

In other words, if caught early, thiamine deficiency is almost always reversible. Due to medical neglect, I went two and a half years without appropriate treatment.

Only the accidental finding of a book has been responsible for my “almost” recovery. So every day, I have to swallow eight pills to over-saturate my body with high doses of thiamine and also magnesium in order for my cells to function properly. Toxicity symptoms—although no longer crippling—still present themselves on a regular basis. I’ve learned to push through, to manage, to rest more if I’m having an “off day.”

Overall, I felt like I got off easy compared to so many other people suffering from adverse drug reactions, but it still hits me sometimes—the “what if’s.”  What if my doctors hadn’t forced me to continue taking metronidazole?  What if they had recognized the toxicity symptoms early on?  What if they—medical professionals—had researched the drug (surely better and faster than I could have given their medical degrees) and discovered the connection between metronidazole and thiamine long ago?

What if they had simply believed me?

And that’s the scariest part. For two and a half years, I suffered from a chronic illness that was not only very real, but also very treatable. However, because of the ignorance (and sometimes arrogance) of conventional medicine, patients like myself are forced to suffer. We are sick in a way that is inconvenient to doctors and their beliefs in their own medical dogma.

There are some scars that will never heal. My faith in medicine has been shaken to its core, and now that I’ve finally been able to see the medical structure from a different angle, it is obvious that medicine is more like a house of cards than a mighty castle. Doctors scare me now, not because I think they are bad people, but because of one simple truth:

Doctors are in denial.

They are in denial of the drugs they give to us every single day.  My story isn’t an isolated incident.  When it comes to drug reactions and how the medical community responds, my story is—unfortunately—the norm.

“There are four conflicts for a patient who has suffered side effects from Flagyl,” explained Dr. Lonsdale.  “The first is finding that the doctor simply denies that the complex symptoms are the result of a prescription drug and accuses the patient of imagining them. The second hurdle is the difficulty of comprehending that their body has been deprived of thiamine by the action of the drug. The third difficulty is understanding that the toxicity will last as long as the thiamine deficiency exists and that it is not a matter of taking a few vitamin tablets. The fourth problem to be experienced is that, if and when the patient starts the megadose thiamine, the symptoms may get worse for an unpredictable time before they get better. There is no doubt in my mind that Flagyl is dangerous enough to be discontinued. This form of toxicity needs understanding by a physician who can take responsibility for its treatment.”

If you’ve suffered an adverse reaction to metronidazole, you’re not alone.  Learn more on my blog.  For victims of metronidazole toxicity or family members trying to find ways to help loved ones with the toxicity, join the Metronidazole Toxicity Support Group on Facebook (you need to answer a question to join).

If you have suffered from the side effects of this or others drugs and would like to share your story on Hormones Matter, contact us.

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Photo by Jr Korpa on Unsplash.

This article was first published on September 9, 2019.


Erin Jensen graduated with a Bachelor's in English from the University of Kentucky in 2004, under the tutelage of authors Gurney Norman, Janet Eldred, Judith Moffett, Nikky Finney, and New York Times bestselling author Kim Edwards.

In 2005, her first fictional short story was published in Tales of the Talisman magazine, and she has since had over a hundred nonfiction articles published in Living Well 50 Plus Magazine, The Human Resource Magazine, Health & Wellness Magazine (a medical magazine for general readers), and Kentucky Doc Magazine (a medical magazine for physicians).

In addition to publications, she has also been a writing tutor at the Carnegie Center for Literacy and Learning, and is the facilitator of The Lexington Prose Group for aspiring authors.

She currently lives in her hometown of Lexington, KY.


  1. I was given Metro in August for Cdiff after bad insomnia, no appetite. Still dealing with both and it”s April. Insomnia caused panic and anxiety was given Remeron in November stopped in March to many side effects. Now take ashwagandha and gummy to sleep and wake up 1:30 or 2am and take Ativan which I do mot want to keep taking. This Med Metro did this to me and everyone says it Anxiety. I”m not driving right now only sometimes with fiancé in car. Working only a few hours. Now Gyno says maybe hormones! Its been 7 months!!!!

  2. Hi there- stumbled across this site while frantically googling Metronidazole and it’s effects. Let me back up a bit- a year ago, I had a case of bv. Gynecologist prescribed Metronidazole . It cleared things up and I finished the prescription . Later on this last spring I started feeling very strange, heart palps, chest pressure, fatigue, brain fog, headaches, and the worst anxiety out of no where. Fight or flight , depersonalization detached feeling, a feeling like I can’t come up with words or say them ,loss of appetite and weight loss , although for me I welcomed that since I have been over weight after baby. I’ve had Depersonalization before from marijuana use and i believe it’s semi related to my chronic sinusitis . But still – something was OFF . Not myself at all! I was even afraid of driving and social settings because of the anxiety and detachment confusion feeling. Anyway it’s been going on for a year on and off. I thought I was crazy and didn’t not know what to do. These symptoms are in and out and I’ve learned how to live with them( meditation and rest) but I’m still fighting it and feel like I’m forever plagued. Fast forward to just this week, had another case of bv, they gave me Metronidazole again and this time , on the third day taking it, I start feeling really horrible again like a bad flare up just tonight, chest tightness, out of body feeling and anxiety ramped up, confusion, weird burning sensations around my neck. I literally went to lie down and started googling ( health anxiety no no) but I felt it was the Metronidazole causing this. I saw your blog and article on this stuff. My question is – can the symptoms show up months later after taking it like it did the first time?? I only had b complex available at my house so took it and starting feeling more normal. Calling my gynecologist and seeing if they have anything else for bv. I feel like this makes sense.

  3. Can someone please help me. Ive beens ruined by metro. I’m 16 months out and I’m still a mess. My blood work showed my thiamine is normal along with all my other vitamins. Should I still take thiamine? Please help, I’m at my ends wit and can’t get no help but antidepressants….. Smhhh

    • Hi Chrissy,

      How are you feeling, have you gotten any relief? My mum is suffering with a relapse from Metronidazole and i’m desperate to figure out a solution.. It’s heartbreaking and there seems to be no answers..

      • Alexia. I’m sorry for you mother and for everyone else going through this..I have made some progress over the years. But it’s still here. Anxiety, depression, detached. My life has been ruined. I’m sorry to write this but I’m being honest. it does get better but never has gone away for me. I hate it… I am so scared to take antidepressants or anxiety medications due to what metro done to me. Side effects scare me. But I’m fixing to have to do something. I can’t keep living like this. Again it does slowly get some better. Hang in there with her because it’s a terrible thing to go through… No body believed me. No Dr had ever heard of this happening. But thousands and thousands of people it’s happening to. Wish I could be of more help. Prayers for her as well as for everyone this has effected.

  4. This type of behaviour by Drs is so asinine; our healthcare systems the world over are broken. Although I wasn’t affected by Metronidazole, it was Lupron that nearly killed me, that and drs ignorance surrounding side effects. It took 11 trips to the ER before someone called the makers of that drug, got verification that it does cause breathing problems due to the lungs filling up with fluid, the company knew about it occurring in the drug trials but any further information was protected by court ordered seal…WTaH! This gave the ER dr permission to dismiss my symptoms despite documentation of those symptoms with the drug company. To me it seems like patients are battling a triple edged sword: kids with no interest in medicine / health / people skills being pushed into becoming drs by families with money, pharmaceutical companies being allowed to substitute drug information as comprehensive disease information and physician colleges using that biased information without performing due diligence to see what is not only evidence based info and including input from patients with the disease / side effects. Two other things that don’t exactly help the situation are kickbacks from pharmaceutical companies to Drs for writing prescriptions / donations made to medical schools and legal protection institutions to protect Drs. Here in Canada, the Canadian Medical Protection Association makes sure nobody can win a case against brought forward against its physicians. I thought we had laws against this type of bias here, but sadly we don’t. Who would have thought that in the 21st Century we would have worse medical care because our healthcare system is so corrupt. It’s maddening, it truly is. I almost died, probably would have if I agreed to take that 4th injection of Lupron; my daughter would have to grow up with out me in her life—it’s a scary thought. What really angers me is that someone is make money off this nice little cozy set up; Pharma with sales and Drs from the kickbacks for writhing these prescriptions—no dry wallets on their end. Don’t get me wrong, we need pharmaceutical companies, but there needs to be clear, legislated boundaries on their connections with medical institutions. It’s pretty bad when we NEED legislation to stop this.

    Hopefully you’re experiencing better days and wishing you a full recovery.

  5. Hi Erin – I would love to hear more on your experience with mirtazapine. I am 7 months out floxed and I have three little kids and the anxiety/depression/insomnia is debilitating. My functional med doctor thinks I need to go on one so I could stabilize and get my body to heal because I am stuck in flight or fight.

  6. I’m not Erin, but I wanted to chime in to give you a heads up about another harmful family of antibiotics called Fluoroquinolones. These include Ciprofloxacin (“Cipro”) and Levaquin. If you do a little googling, you’ll find entire communities of people who have suffered persistent physical and neurological symptoms from them that are eerily similar to what the author described above. It even has its own term; being “floxed”. For some people, just one or two doses can be enough to permanently change their life. I have no idea if it also has to do with Thiamine, but there are hypotheses of it being related to severe magnesium deficiency in tendons, joints, and nerves, and mitochondrial damage.

  7. Hi Erin

    I was perscribed metronidazole for H-pylori and parasites… I have been putting off taking it or a year and trying natural protocols… I am now deciding between constant pain in my stomach or the drug protocol including the metronidazole. I dont want to take it… are there any antibiotics that I could take that would be ok and not cause the B1 deficency… is it only this class of antibiotics that has these side effects? Im desparate to feel better and heal H-pylori but not willing t take the metronidazole. thanks

    • Warning!!! Don’t take this metronidazole antibiotic for H. pylori. It ruined my life. I was also diagnosed with H. Pylori and this antibiotic caused all sorts of extreme side effects which I reported back to my doctor. Really extreme like daily headaches, slurred speech, hand tremors, forgetfulness, skin turning darker with new moles, all sorts of cognitive dysfunction from inability to just add 2+3, or not being able to comprehend the letters on the car gear shift. Stay away from the medication if at all possible. I have seen multiple doctors who have denied these long-lasting effects and diagnosed me with severe depression and anxiety. It is almost a year now and I’m still not 100% myself. My job, my marriage, my family, all my relationships, my house, my liveliness is hanging on a thread because of this medication.

  8. I’m pretty sure that reading something you’d written before was the catalyst for me to begin using allithiamine. The functional medicine doc i work with had determined B-vitamin deficiencies and MTHFR gene mutation before. I had tons of thiamine HCl and thiamine mononitrate in the house, but they did nothing for me.

    By the time i read about allithiamine and ordered it, i was only able to stand or sit upright for 15 minutes, a few times of day. I was sure that by now i would be bed-bound. It was some type of dysautonomia, but it was not POTS nor orthostatic hypotension. The allithiamine has been an amazing find. I’m now able to be up for an hour or more a day. I’m still dealing with significant fatigue. I stopped trusting the medical profession quite a long time ago (like sometime between 1998 and 2003). I’m pretty sure that 90% of what i’m dealing with is iatrogenic, and far more than Flagyl. It started with fluoride when i was young, and just kept getting worse, especially after they talked me into being a psych patient with tons of psych meds – none of which helped. I now know that many of these had a fluorine component, so they just kept poisoning me.

    I’ve tried benfotiamine, also, as that is supposed to be well-absorbed. I was using both because i could get benfotiamine in 200 or 250 mg capsules, so i had to take fewer pills. I’m leaning toward thinking that allithiamine is the better one for me. I’m taking enormous doses. I was already taking about 400 mg thiamine in benfotiamine and allithiamine first thing in the morning, and more in the day if i started feeling dizzy. But based on this info from Andrew Saul, i began taking much larger doses a couple of weeks ago.

    I’ve known of Andrew Saul for a long time. I began taking the thiamine, niacin, vitamin C, and magnesium. I was desperate to have more energy.

    After a few days of this protocol, however, i began having issues. I recognized it from when i’d used 5-HTP with disastrous results. I think i had a form of serotonin syndrome, although milder than what i would have had with a pharmaceutical. Because of that i knew where to look for some answers. There isn’t much out there available, but i found one study that showed diets deficient in both thiamine and magnesium to not have elevated serotonin, but those deficient in magnesium but not thiamine to have elevated serotonin levels. Extrapolating from that i realized that i need to be taking much more magnesium. I was very close to suicidal last Tuesday, but recognizing the symptoms of serotonin syndrome helped me to find a way to balance things.

    Anyway, thank you for your story. Reading about using allithiamine has been the beginning of the first improvement i’ve seen. I’ve been dealing with this most of my adult life. It is very discouraging.

  9. I’m an ICU nurse and I just want to apologize for the failure of the medical professions around you. Maybe it’s because of my training but I am inclined to listen to patients rather than refuse to believe them. I run into this often when a patient states they are in severe pain and the physician says ok well let’s do some Tylenol. I say no let’s start something stronger and they flat out refuse to believe the person is really in pain because “you just don’t have that kind of pain with that condition”. To which I state they aren’t the one with the condition so how the heck would they know what level of pain would be involved and even so not every case is going to be the same. I’ve been in that position myself- where a med needs a delicate hand when stopping it and the physician refused to believe it couldn’t be done over a week. I suffered for a long time because of the refusal to believe something despite medical research I showed the physician. It’s sad and people who can’t use common sense and overly rely on training and a refusal to step outside the box just shouldn’t be allowed to practice medicine or pharmacy or even nursing for that matter.

  10. Dear Erin,

    I was floxed 5 years ago, sice than I received few stem cells treatments that helped me. I want to ask you a question related to the antibiotic I took yesterday and that made the bad reaction in my body. I had my tooth extracted yesterday and the doctor who is actually treating my neauropathy in holistic clinic prescribed me metronidazole. The correct name of the antibiotic is Rhodogil, it contains Espiramicim and Metronidazol. The doctor told me this is the best one for me because it wont ruin my gut, after 15 minutes of taking I had side effects, not very severe but still I didn’t sleep whole night. My burning in head, ear ringing, weaknes and numbness in arms and legs increased and other symtoms such as diziness and feeling sick. I did again mistake not checking out on floxie hope which antibiotics I can take, and today in the morning I saw on floxie hope that metronidazol is similiar to cipro ? or he has similar side effects. I’m in total shock now. I saw reviews of this antibiotic, and they are bad, is this om level of Cipro and Levaquin or is it not that bad? I don’t know what is going to happen now, I did last stem cells a month ago here in Spain and was slowly improving and now this one tablet yesterday made a reaction, now in the morning the side effects are there, many of them. I just want to ask you how bad is this antibiotic? Was this horrible mistake that I took one? I know you probably cannot amswer me everything but I just hope for some words of comfort because like I said, I am in shock. I really hope I’ll get response from you.

    Thank you in advance.

  11. I’m wondering if part of what happened is a bradykinin cascade. When taking Lisinopril I had an adverse reaction that included heavy coughing, a tightening in the chest and shortness of breath. This continued for quite some time after stopping the drug. It also seemed to trigger more after eating and there was a bit of itchiness/tingling like an allergic reaction in the lungs.

    Bradykinins are hard for the body to process and it tries expelling them through the lungs.

    I had good results getting rid of them with bromelain.

    Interesting info showing the bradykinin cascade, granted this is on angioedema but the cough/tightness/shortness all preceded the angioedema for me (scroll down for the bradykinin spiral chart)

    ehealth reports that there are adverse reports indicating flagyl and angioedema indicating possibility of bradykinins in adverse events. Its rare but angioedema is the extreme. More people report the cough (2.36%), chest tightness (3.68%), and Shortness of breath (5.3%) so bradykinins could be involved and in my experience they persist long after stopping the drug.

  12. Hi, I still have some breathing issues, chest tightening, fatigue, leg weakness, slight internal tremor in left arm, lightheadedness, brain fog, and neck pain/stiffness. However, they are very mild most of the time, where I might only have one or two symptoms on any given day, and just slightly. Some days, I’m 99% symptom free. If I do have a flare up (most symptoms returning at once), it’s usually very short-lived, a day at most typically, and again, very mild. I can still go to work, run errands, see friends, etc.

    I’m glad your symptoms are mostly gone, but I understand the frustration of being dependent on a pill now, even if it is a supplement. What I do is just remember that I’m dependent on a lot of things–food, water, air. I drink kefir daily to keep my gut happy, but if I stop, then after a week my IBS can return. It’s just another thing that’s needed to keep your body healthy, so if you do have to take it for years or even permanently…it’s okay.

    • How much thiamine did you take at the most, and how much do you continue to take? Did you find it increased your need for potassium? High dose thiamine is the only thing helping my breathing. Thanks.

  13. Hallo erin,
    how are you today? what symptoms do you still have post flagyl? I am a cipro + flagyl victim and have been taking thiamin hcl for 5 months. My ataxia and dizziness are gone. have only slight brainfog. Unfortunately, when I reduce thiamine, my symptoms of Zn return.

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