Fast Diarrhea Relief!! Metronidazole: Seeing Past the Research

Damn the Casualties, We Want a Fast Fix!

There’s a new treatment to beware of. It typifies that short-sightedness of conventional medicine that brings a flame thrower to a bothersome mosquito problem.

Just as antibiotics are the most mis-prescribed and over-prescribed class of drugs in people and pets…

At least 30 percent of antibiotics prescribed in the United States are unnecessary, according to new data published today in the Journal of the American Medical Association (JAMA) by the Centers for Disease Control and Prevention (CDC)1

… so, too, is Flagyl, aka metronidazole.

I frequently hear its use from many clients and from many who read and comment on this blog.

Flagyl’s claim to fame is “fixing” diarrhea.

And it does, sort of.

But like with all antibiotics, at a cost to your animal that you’ll want to be aware of.

World Wide Concerns

Just to give you a sense of how “on the mind” metronidazole is around the world, the term is being searched for in almost every country on the globe


Might this be due to concerns about the drug?

I’m guessing so.

Antibiotics: High Precision Killers?

I suspect you know the answer to this. Phrased another way, the important question is,

Do antibiotics only kill the “bad germs” and leave the beneficial ones alone?

Why is this such an important question?

Well, we’ve known for a number of years now that we have a huge gut population of “good guy” bacteria resident in and on us all, animals and humans.

And, we know the proper balance of the gut microbiome is critical to our health.

Just to remind you of the good that comes from our healthy gut dwellers alone, they:

  • aid digestion and the extraction of energy from consumed food
  • are responsible for B vitamins, vitamin K, and the production of amino acids and fatty acids
  • nourish the cells they live close to, the lining cells of the gut wall
  • help immunity (some say that the gut has MOST of the immune system)
  • offer a barrier against pathogens invading

It turns out that diversity is greatly depressed when an animal or human is ill. Both show less species when chronic diarrhea or inflammatory bowel disease is present.2

The answer to this key question is a resounding “NO!”

Antibiotics, metronidazole included, kill indiscriminately. Good flora right along with pathogens, the “bad bugs.”

Notably, metronidazole reduced bacterial diversity indices in the present study. Decreases in microbiota of bacterial diversity have great importance in humans. The use of antibiotics often results in antibiotic-associated diarrhea (AAD), which is due to the disruption of the GI microbial ecosystem and subsequent overgrowth of pathogenic species…3

Enter The “Faster Fix”

I received a postcard from Nestle Purina this week, touting a faster recovery from “kennel associated diarrhea” (my term for the disease studied) when metronidazole was given together with their probiotic called FortiFlora.

Digging deeper, it appears this combo saved about a day of diarrhea in these stressed dogs compared to giving metronidazole alone.


But, I’d suggest we drop the metronidazole and favor probiotics in these “stress diarrheas,” as metronidazole clearly disrupts the good gut flora.

Your Best Bet

Since we know all antibiotics cause gut problems, it’d make good sense to choose other avenues to help diarrhea animals recover.

That’s especially true if the diarrhea is a chronic (long-lasting) symptom.

What’s better than antibiotics?

Curing the “whole animal” with the help of a qualified homeopathic vet.

That’s true in all long-lasting diseases, by the way, diarrhea being only one. When we get the whole animal well, the diarrhea naturally goes away.

While your homeopathic vet is pursuing cure, probiotics make good sense to add regularly to the diet.

Although it appears Purina’s FortiFlora has some good, measurable outcomes, their first ingredient is “animal digest.”

Oh, my.

Better than “animal” is something recognizable, which is why for a few decades now, I’ve recommended Wysong’s AddLife.

Its first ingredients:

Enzymatic Digest of Chicken and Fish, Chicken…4

I know what a chicken and a fish look like.

Animal digest? That could include euthanized dogs or horses (and yes, those have been found in commercial pet foods, right along with the pentobarbital used to put them down).

So, yes, probiotics are good for your pet. Animal digest? Not so much.

If you’d like a copy of my latest “vetted” list of homeopathic vets (who can help you whether they live near you or not), here’s where you can get that:

Tell us in the comments if you’ve experienced either metronidazole’s effects or probiotics’ effects in yourself or your animals.

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  1. Neil on June 20, 2020 at 12:26 pm

    My 12 yr old Shitsu (female) has never had diarrhea “ever” until she started a bout a week ago. Am currently visiting my daughter so she’s out of her normal environment After 3 days of continuous runny poop I decided to take her to a vet. Vet prescribed liquid Metronidazole 50mg to be taken by mouth every 12 hrs with food for 7 days. After 3 days with a recommended bland diet (lean hamburger and rice – equal portions) and the medication, she’s come around and now back to her same old self. Should I stop the medication as all appears normal, or should I fulfill the recommended 7 days of meds?

    • Will Falconer, DVM on June 20, 2020 at 11:47 pm

      It all depends how far you want to disrupt her gut flora, Neil. Those effects can last a long time, and include digestion, immunity, and even behavior. If she were mine, I’d stop and get some green tripe added to her diet regularly. Like a teaspoon’s worth daily, small as she is.

      • Lynn Lassen on April 14, 2024 at 2:47 pm

        Love green tripe!

  2. Dana Flemming on May 22, 2019 at 9:02 pm

    This drug was prescribed to my Collie and he suffered severe neurological effects from it. He was disoriented, frantically chewed his tail with such ferocity that we could not pull him off, ceased eating or being aware of his surroundings. He did not respond to his name when called.
    Our vet really didn’t know what to do…
    After much desperate research we discovered that a benzodiazepine, such as Valium or Xanax could reduce the recovery time by somehow causing the toxic aspects of Flagyl to be released from the receptors in the brain more quickly. This reduced recovery time to approximately 2-3 days. He was placed on 4mg of Xanax a day until the side effects subsided.
    Either way, it was dicey, scary and we would never put our dog through this again.

  3. Lauren Campbell on May 17, 2019 at 8:02 am

    Hello, regarding Purina Fortiflora vs. other brands of probiotics with better ingredients, I wanted to inquire….

    I switched my puppy to a different brand from the local natural pet foods store with “real” transparent ingredients. It comes in a little bottle similar to the Wysong product you recommended. When I went to a vet for follow up on my puppy having bloody loose stool, he explained to me that over time, probiotics that aren’t sealed in small packets lose their potency to the point of basically nothing at all when it continues to hit air. Do you have any thoughts on that?

  4. Jessica Egli on May 15, 2019 at 4:09 am

    My 10 year old pug Bruno was given Metrobactin (Flagyl in the UK) due to a suspected giardia infection. At that point he had really bad diarrhea for almost 3 weeks, lost 2,5kg as he stopped eating anything and the vets just could not get the treatment right. They did a blood test on him, an ultrasound checked his temperature and felt his tummy a million times but missed to check any fecal samples. In the end the prescribed Metrobactin as they clearly not listened to us when we told them repeatedly that he tends to have allergic reactions to many drugs (simply the annual injections knocked him out several times). Within 2 days he had strong toxic reactions and died 2 days later due to liver failure. We paid £3,000 to them for killing our dog and till the end they deny that this was a toxic reaction to the medicine as is it only proven to cause exactly those reactions but only after using it for 2 or more weeks. They claim that he simply must have had a more serious condition like blood cancer but absolutely nothing, besides their assumptions, speaks for it and they have zero evidence. We are still fighting them but obviously our chances are more than low. Nonetheless, we do not want to give up. In the meantime we have been contacted by a family in our neighborhood whose beloved dog died only 3 weeks before our lovely pug Bruno after having diarrhea and being given the same drug with almost the same toxicity symptoms. They were with a different vet but their dog was also know to be sensitive to drugs and they are also trying to fight theirs.
    There must be so many more cases out there. Why is nothing done against this drug and all the beloved family pets dying from it?
    Do you have any idea what else we could do? Whom else we could reach out to? We have already submitted a complaint with the pharma company supplying the drug in the UK and a yellow label warning has been raised in the UK but of course nothing else happens as the vets claim they did nothing wrong, it can’t have been the drug, the pharma company claims it was probably not the drug… and we can’t prove it. But I know! I knew my baby for 10 years and I know exactly how he reacted when he was given strong drugs… There must be more we can do to raise awareness and to get justice.

  5. Diana Baker on May 5, 2019 at 9:08 pm

    Hi, I’m so happy I found your website. I have a 12 week old French Bulldog puppy who started to regurgitate fluids numerous times a day – sometimes small amounts, sometimes large amounts, within 24 hours of receiving his second set of vaccinations. We had only had him for 3 days prior to that. He seemed perfectly healthy until he was vaccinated. I’ve taken him to 2 veterinarians and he has had several sets of X-rays with barium. No abnormality was found. He was put on Reglan, and Pepcid. The regurgitation has stopped but he then developed diarrhea. It has been 10 days now. He just finished a course of Metranidazole. It didn’t really help and now I’m sorry I gave it to him.

    I should also add that the breeder told me he and his litter mates were treated for Coccidia when they were six weeks old. His records show that at his six week check up he was dewormed for the second time, vaccinated against distemper, adenovirus, parvovirus and paroinfluenza. He was also treated with totrazinil for coccidia. That seems like an awful lot to throw at a young puppy! He had all of the same vaccinations at 9 weeks. After reading your article I’m thinking this all started with the first vaccinations. He has a lot of energy and seems to be thriving aside from the GI issues. He is due for his third vaccinations this week and I am very concerned about hitting him with all of that. Especially in light of the GI issues.

    That was a rather long winded way of asking you:
    1) do you know of a holistic vet in the Lexington, KY area?
    2) what would you recommend to get my pup’s gut flora normalized?
    3) what should I do about further vaccinations? Would individual vaccinations spaced out be a better idea?
    4) I’d like to start feeding him and my other dogs a raw diet and don’t know how to transition him. I feed my older dogs a freeze dried raw diet with a little kibble and some raw meats I buy frozen that are specifically for dogs.

    Finally, I’d like to add that my 2 year old French Bulldog started vomiting after her last vaccinations but when I brought it up to my veterinarian he said the two were unrelated.

    Many thanks in advance for any info you can provide.

  6. Will Falconer, DVM on April 24, 2019 at 5:10 pm

    Hi Helen, the best bet is to hire a homeopathic vet for this dog. One whose practice is mostly or only homeopathy and, if none like that near you, one who’s willing to work by telephone as well. The goal is CURE, whole dog cure, diarrhea, liver, lethargy, everything.

    As you may have guessed, nothing in conventional medicine can offer this. And, as you’ve seen also, one drug can lead to another, to another, etc. See my Resources page for the AVH list and do a search. Good luck.

  7. Helen on April 16, 2019 at 8:48 pm

    My sheltie is on metronidazole 250mg for diarrhea,he also is having liver issues and is on denosyl 225mg. He doesn’t want to eat,is drinking water,very lethargic..What do you suggest, been to the vet 2x..Thank-you,Helen

  8. Dana Flemming on June 1, 2018 at 9:23 pm

    My Collie (Dylan) recently had an anal gland infection. He was given Flagyl. After only 3 days on this medication Dylan began to bite and chew his rump and hindquarters in a super frenzied manner. He also appeared to be suffering from mental confusion, disorientation, bizarre behavior and he was whining while both awake and asleep. I stopped the Flagyl after 3 days. A second veterinarian diagnosed neurotoxicity due to the Flagyl and prescribed a benzodiazopine since this medication has proven to help reverse the effects of neurotoxicity from Flagyl in a much shorter period of time as opposed to recovery without it (hours versus days or even weeks). I called Washington State University since my Collie has the MDR1 gene and is mutant/normal. They stated that to date, no connection has been found between the MDR1 gene and Flagyl. Regardless, I totally regret ever giving Dylan this drug and the second veterinarian wondered why Flagyl was even prescribed for an anal gland infection in the first place. End of story…this is a very, very scary drug!

    • Will Falconer, DVM on June 2, 2018 at 5:46 am

      Glad you resolved this, Dana. You were wise to stop it. I, too, saw an immediate red flag: Flagyl for anal glands?? May be time to either have a sit down with that first vet or simply fire him and find someone better.

  9. Karen on March 30, 2018 at 9:51 am

    My almost 11 y/o Scotty recently had extensive dental work, and had many teeth removed. His teeth were always bad, from puppyhood on. He was given the usual course of antibiotics, and also what seemed to me, a long course of flagyl… Jack had a rough recovery, and started to not want to eat. It seemed like every other day or two, he was listless, and refused to eat. Having 3 other dogs, and being in winter where they would go out to their pen to “do their business” , it was difficult to see that his poop was looking like. His ck up afterwards was good in the respect that his sutures were healing up well, and his mouth looked very good per the vet. I mentioned to the vet I wanted to take him off the flagyl, I hadn’t been giving it to him regularly, as I was leery of it, but she said she wanted him to finish the course. So I started giving it to him again. The same thing started. He was listless, no appetite, pawing at his mouth, and bloody diarrhea! I couldn’t figure out what was happening, his prior bloodwork was good, and I was giving him a bland, home cooked diet when he wasn’t feeling well. I didn’t know what to think, Finally – I was reading some of the side effects of the flagyl, and there it was – all his symptoms. I called the vet office & told them I was taking him off the flagyl myself, as he was not tolerating it. I gave him a little pepcid AC, and put him on the bland diet, with some canned organic pumpkin to control the diarrhea. It took almost 2 days, but Jack is eating again, doesn’t seem as lethargic, and more like himself. No more flagyl for this boy!

  10. Janet R on November 27, 2017 at 3:06 pm

    Hello Dr. Falconer, My GS “China” and I were one of your early clients in Travis County, Texas. I came to you because she stunk to the high heaven–especially in her ears— and she’d lost so much hair and weight. People didn’t want to be around her and/or they felt we weren’t feeding her enough. But I was feeding her Science Diet as the vet said I should. Immediately you put her on a 3 -day ‘milky’ fast, started homeopathic treatment and taught me how to feed a raw diet. We also had “Crash” the cat, a stray that found us– who you saved.
    — Today we live in Berkeley area and now have “Queenie” a 7 month old terrier-lab puppy we adopted from a shelter when she was 8 weeks old. She’s upended life– in funny ways (and not so funny ways, sometimes).
    1. do you have a recommended raw food diet protocol? No longer do I have the recipe you gave me 24 years or so ago.
    2. What do you recommend for anti-doting against the innoculations she’s had thus far (parvo, etc plus rabies) ?
    It’s great to be back in contact with you.
    Janet R. (formerly of 2019 Calle Caliche, Austin)

    • Will Falconer, DVM on November 27, 2017 at 9:55 pm

      Hey Janet,
      Wow, you’ve dated me now! A “milky fast?” Must have been about 20 years ago… Ha! Glad it all worked out for you. Kind of remember Crash.
      As to your newbies, I don’t have a recipe per se these days (I find them dangerous: too easy to never change them up!). Here’s a starting page that’ll get you some direction.
      No “universal antidote” for vaccine illness, I’m afraid. Best is to hire a homeopathic vet. Or see my special for pups on my Contact page. I’d love to help you again, just limiting my practice quite a bit as I focus on teaching smarter prevention these days. Oh, and distance matters not with this work.

  11. Paulina Pham on November 7, 2017 at 7:58 pm

    My Yorkie has chronic pancreatitis/IBD. He gets an attack about every 6 months, but it has been happening more frequently now. Every time we take him to the vet they just prescribe metronidazole and purina fortiflora. Unfortunately, there are no holistic vets around us. What brand of probiotics do you recommend?

    • Ter on November 10, 2019 at 7:10 pm

      I have the same problem. My 16 year old Snowshoe Siamese had pancreatitis 2-3 months ago. The vet prescribed metronidazole and it helped but every time I try to get her off of this, her stools get loose. She is still on it and now she has watery diarrhea for 2-3 weeks! They just prescribed another antibiotic as an “anti diarrhea “ med on top of this. After one week if no improvement. I’ve taken her off of it despite the vets encouragement to stay the course. How can I get her off if the metronidazole and also stop her existing bad diarrhea? Can prednisolone help to support my cat while I’m trying to reduce the antibiotic? I regret saying yes to this suggestion.

  12. Beverly Villarreal on September 19, 2017 at 8:28 pm

    What do you recommend while an animal is being treated with an antibiotic? I’m working with a small Austin dog shelter that took in dogs from rescues in the path of Hurricane Harvey. A couple of them are experiencing diarrhea, one consistently with some blood. Another dog has been on antibiotics for 2 weeks due to a gash, but his poop is well formed. Vet prescribed metronidazole today. I give my own dog 1 21st Century Acidophilus Probiotic Blend each day ( human grade), but since antibiotics are nondiscriminate, would it be better to give 2 to dogs receiving antibiotics? I don’t suppose that anyone knows how much of the 1 billion live cultures delivered by one dose would survive antibiotics, but the strategy is to flood the system with good bacteria so once the antibiotic course is finished, the good microbes have the edge for establishment.

    • Will Falconer, DVM on September 21, 2017 at 11:11 am

      Just no telling if lots of probiotics will help the damage done by the antibiotics. Worth a try, and I’d certainly recommend long term probiotics after antibiotic therapy, as in months, if not for life.

  13. Dawn Skura on September 17, 2017 at 10:31 pm

    I have an amazing homeopathic vet. How can I get her added to your list?

    • Will Falconer, DVM on September 20, 2017 at 1:30 pm

      Hey Dawn, I had my team search out those homeopathic vets from the AVH site who did only or 75% or more of their practice in homeopathy. And, they offered telephone consulting. As many misunderstand that “homeopathy” and “holistic” are two different things, I reviewed their findings to recognize the choices were all well trained and several certified by the AVH.

      • Ellen on September 20, 2017 at 4:09 pm

        Thank you for pointing this out. We have one in our state who claims she is “holistic” (she’s not on your list so don’t worry!) yet on her website she talks about vaccinating in a safe way with mercury free vaccines and so on. Give me a break. That is one uneducated vet. Vaccine reactions are due to the entire vaccine not just the preservatives. There is no safe way to vaccinate imo and some vets seem to use “holistic” as a marketing ploy. I don’t understand how ethically doctors can shoot these poisons into pets and people. What a disgrace.

  14. Yvonne Donner on September 17, 2017 at 10:17 pm

    Our integrative vet recommended Proviable paste to alleviate the diarrhea along with their probiotic capsules for maintenance. It worked in a couple days. I also use the Addlife and Feline Transfer Factor.

    • Will Falconer, DVM on September 20, 2017 at 1:31 pm

      Nice! Presuming that means no antibiotics?

    • Ter on November 10, 2019 at 7:01 pm

      I’ve tried the proviable paste for bad diarrhea w 2 of my cats with no success!
      How can I get my 2 cats with pancreatitis off of metronidazole? I regret my vet putting them on this! Every time I try to reduce the pills, things get worse.

  15. Nora C on September 17, 2017 at 8:37 pm

    Rebuilding the gut flora after antibiotic use is a tough-y. I liken antibiotics to voodoo; ya just shouldn’t…run the other way!
    I gave Pookie FortiFlora just about every day and it did help some, but the gut busting effects of vaccines, dead foods and man made meds is nearly impossible to overcome. I don’t think the people making these probiotics really know enough about balancing the microbiome or the specific strains of bacteria that need to be replenished to restore health, and some are far too apt to use questionable sources because of the profit involved. (I’m not talking about Dr. Wysong’s stuff, though. I think his products are generally good, although I haven’t tried AddLife.)
    My beloved little Pookie cat passed away at 9:15 am July the 6th, after beating the odds for three years and four months. Like many Siberians, she had hypertrophic cardiomyopathy, she was never robustly healthy. She was diagnosed with cancer in 2014. I put her on a raw organic diet and the best supplements I could find, and towards the end I gave sub dermal fluids every day to keep her hydrated–her kidneys were failing. She was just shy of 16, fairly old for a Siberian. The one thing I couldn’t overcome with love and food was old age. I’m a bit lost still…no one ever loved a cat more than I lover her. I took care of her around the clock for three years, and would gladly have done it longer. So here is a testimony; food is the only medicine your dog or cat needs, besides a well chosen, occasional remedy from your homeopath. Skip the antibiotics, the vaccines, the “dental cleanings”, the toxic flea and worm products and feed ’em like doc says. They’ll be with you longer if you do, and they’ll be robustly healthy and vital.

    • Will Falconer, DVM on September 17, 2017 at 9:27 pm

      Ah, Nora, I’m so sorry you lost Pookie. She was undoubtedly your best teacher and your closest companion.
      If you’re feeling a bit lost still, you might try a dose or two of Ignatia 30C. Was just reminded by one of my Alpha students today how miraculous that can be when the emotions are whacked by loss.
      All the best to you, my dear.

      • Nora C on September 18, 2017 at 12:05 am

        Thanks, doc. I credit you, with all you taught me, for her lasting so long despite her illnesses. I see the wisdom every day in feeding them right, the way nature intended. Dr. Whitecoat told me bitterly one day, that she only got three months with her cat after a diagnosis of cancer. She fed kibble, vaccinated and flea-treated her cat into an early grave, and just doesn’t get it, why Pookie lived three years instead of three months. If not for your Vital Animal blog, I wouldn’t have enjoyed the extra years. Thank you for being a great teacher and a blessing. (big cyber hug!)

  16. Kathryn Foster on September 17, 2017 at 6:37 pm

    I sure do miss seeing you on Facebook Live Video. I know you have a larger task at hand right now, but I just wanted to tell you that I miss you.
    Your friends in North Carolina,
    Kathryn Foster and English Setter, Hank
    P.S. Hank is on his second remedy from Dr. Jennifer R. from your list. He has been raw fed since 12 July 2017. His itchy red skin is gone now. I am shocked at how much calmer he is now too. We have our next phone appointment with Dr. R on 5 Oct 2017. It has been a bit pricey but I’m committed to sticking with it. I love him that much.
    Thank you and God Bless You Dr. Will

    • Will Falconer, DVM on September 17, 2017 at 9:24 pm

      Oh, Kathryn, I love hearing homeopathic success stories like this! When the “mentals” improve along with the outside stuff, you know you’ve given a deep acting, well chosen remedy! I applaud your commitment and sticking to it till he’s cured. Next thing you know, you’ll be asking your homeopathic vet for a human homeopath and getting similar amazing results for you!

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