Vets may recommend Metamucil® for dogs with diarrhea or constipation because it is excellent at modifying stool consistency. To give you the facts on this fiber supplement, integrative veterinarian Dr. Julie Buzby explains how Metamucil works, which forms of Metamucil dogs should—and should not—take, and Metamucil’s side effects and safety considerations.
When you think about fiber supplements for humans, Metamucil is probably one of the first products that come to mind. Chances are good that you have noticed the classic orange tubs at the drugstore or watched TV advertisements touting the benefits of Metamucil. Maybe you even have some in your own medicine cabinet.
But what you may not know is that this common over-the-counter dietary fiber supplement for humans can make a useful fiber supplement for dogs, too. That said, don’t stop reading this article to reach for the orange container in your cupboard quite yet.
First, it is important to check with your vet before giving your dog any new medication or supplement. Second, it’s important to know that there are some Metamucil formulations (e.g. wafers, gummies, and flavored powders) that contain inactive ingredients that are harmful to dogs. We’ll dive into this after answering some common questions about Metamucil for dogs.
What is Metamucil?
The active ingredient in Metamucil is psyllium, a derivative of the plant known as Plantago ovata. Psyllium is a viscous soluble fiber that is slowly fermentable. This means it dissolves in water to form a gel (i.e. is soluble and viscous) and sticks around in the GI tract rather than being rapidly broken down by gut bacteria. It also produces less gas than rapidly fermentable types of fiber.
Additionally, Metamucil contains certain amounts of insoluble fibers (i.e. those that don’t dissolve in water). This makes it a “balanced” fiber supplement with many useful properties. As such, it is a good first choice for fiber supplementation for dogs.
(If you want to learn more nitty-gritty details about the types of fiber and what they do, check out my comprehensive article on fiber for dogs.)
What is Metamucil used for in dogs?
In certain situations, your veterinarian may recommend giving your dog Metamucil. Since it is a supplement that was originally made for humans, this is considered “off-label” usage. However, it is ok to give your dog certain formulations of Metamucil under a vet’s supervision for treating constipation, diarrhea, or other issues.
Metamucil for dogs with constipation
Metamucil is great for constipated senior dogs and dogs diagnosed with constipation secondary to disorders that cause dehydration (e.g., kidney failure in dogs). Your vet may also recommend trying it if your dog has gone too long without pooping.
The psyllium in Metamucil can be helpful when a dog is constipated because psyllium swells when it absorbs water. You can think about this sort of like adding water to a dry sponge. When the stool (or the sponge) soaks up water, it becomes softer. This makes it easier for a constipated dog to have a bowel movement.
Additionally, the insoluble fiber portion of Metamucil has a bulk-forming laxative effect. In other words, it creates bulkier stools. Plus, it is mildly irritating to the lining of the intestines, which causes a shorter transit time through the digestive tract.
Due to the combination of these two fiber types, administering Metamucil leads to softer, bulkier stools that move through the gut faster. This can help resolve and prevent constipation.
Metamucil for dogs with diarrhea
If your dog has colitis, inflammatory bowel disease (IBD in dogs), or diarrhea, he or she might also benefit from a fiber supplement like Metamucil. Since the psyllium in Metamucil is good at absorbing water, it can also soak up extra water in the stool (kind of like a sponge). This can lead to more well-formed stools.
For example, one study published in the Journal of Veterinary Internal Medicine looked at using Metamucil and the gastrointestinal diet Hills Prescription Diet i/d to treat dogs with chronic diarrhea. Most dogs showed a good to excellent response (i.e. improved fecal consistency). The researchers indicated that 23 of the 37 dogs in the study had been unsuccessfully treated with Hill’s i/d in the past, which makes it likely that adding the Metamucil is what made the difference.
How much Metamucil should you give a dog?
In the above study, the average amount of Metamucil each dog received was two tablespoons. However, the actual dosage ranged from half a tablespoon to three tablespoons, depending on the dog’s size. Since each dog’s situation is a bit different, the best way to find out how much Metamucil to give your dog is by contacting your vet. He or she can give you a starting dose and then work with you to make modifications to that dose as needed.
What kind of Metamucil can I give my dog?
Your vet can also recommend the best type of Metamucil for your dog. This is a good thing because it can be easy to suffer from “analysis paralysis” when looking at the shelf of Metamucil powders, capsules, wafers, and gummies. Here are some general guidelines for you to discuss with your vet.
Stick with unflavored powder or capsules
The safest forms of Metamucil for dogs are unflavored powder and capsules. Not only are these forms the most fiber-dense varieties available, but they also do not contain any harmful ingredients. (Even then, it’s always best to check the label for xylitol or other harmful ingredients.)
Beware of flavored varieties, gummies, and wafers
Metamucil also comes in flavored powders, gummies, and wafers. These flavored options tend to be more unpalatable to dogs and may contain sugars like sucrose and brown sugar, which can cause gastrointestinal upset in dogs. And the sugar-free version of Metamucil (commonly orange-flavored) contains aspartame which can also cause stomach upset.
However, the most dangerous form is the Metamucil gummies, which contain xylitol (i.e. birch sugar) as an artificial sweetener. Avoid gummies, or any other xylitol-containing products, at all costs because xylitol is extremely toxic to dogs.
How do you give Metamucil to your dog?
If you decide to go with unflavored powder, you can sprinkle it on your dog’s regular food. It is easiest to sprinkle onto wet food, but you can also add it to dry food. Sometimes you need to add some water to get the powder to stick to the food. Keep in mind, though, that adding too much water can turn the powder into a mushy, unpalatable gel-like substance.
If your furry friend won’t eat the Metamucil powder or you have a larger dog who needs a lot of powder, the capsule version might end up working out better. You can hide it in a favorite treat or right in your dog’s canned food. Or, in many cases, it is safe to use low-sodium chicken broth or a small slice of banana to entice your pup to take Metamucil.
What are some alternatives to Metamucil?
If you are still struggling to get your dog to take the Metamucil, you can also try some of the tips in my article, Your Dog Won’t Take Pills? Or you may want to reach out to your vet to discuss alternatives to Metamucil.
Metamucil does tend to have more fiber per serving than many other products, but there are other ways to provide fiber for your dog. These include:
- High-fiber prescription dog food
- Veterinary-specific fiber supplements
- Other human fiber supplements like Benefiber (which has less fiber per serving than Metamucil)
- High-fiber foods like canned pumpkin for dogs (Keep in mind that your dog will need to consume a larger amount of pumpkin to supply a similar amount of fiber as a teaspoon or two of Metamucil.)
Your veterinarian can help you figure out the best product and dose for your dog.
Can my dog take Metamucil with other medications?
While talking with your vet about fiber supplements like Metamucil, it is also helpful to mention any medications or supplements your dog is taking. Metamucil can affect the way the body absorbs other medications such as:
- Pain medications (e.g. NSAIDs and gabapentin for dogs)
- Heart medications (e.g., amlodipine)
- Antacids (e.g., omeprazole for dogs)
- Omega-3 fatty acids for dogs
Your vet may recommend giving the medications two hours before or two hours after the Metamucil. This can help prevent issues with poor absorption.
Is Metamucil safe for dogs?
Additionally, like most other medications, it is best to follow your vet’s dosing recommendations. Metamucil is overall safe for dogs (assuming you use a safe version as outlined above). But large amounts can cause diarrhea, constipation, and flatulence. It is also possible for growing puppies to become ill from excess fiber supplementation because it may diminish the absorption of nutrients from their diet.
Also, in rare cases, giving Metamucil without adequate water intake has led to esophageal or intestinal obstructions. Therefore, it is a good idea to try to encourage your dog to drink plenty of water while taking Metamucil. This can help it work effectively and move through the digestive system.
Is Metamucil right for your dog?
Overall, Metamucil is a useful fiber supplement for dogs. It does a great job of helping prevent and treat constipation in dogs and resolve diarrhea. Plus, the side effects of Metamucil are minimal.
However, keep in mind that some formulations (e.g. wafers, gummies, and flavored powders) contain harmful inactive ingredients. Always check the label for xylitol or other problem ingredients before giving Metamucil, or any other product, to your dog.
Also, remember to talk with your veterinarian before deciding to give your dog Metamucil. He or she can help determine if it is the right treatment. Plus, your vet can advise you about the best Metamucil dosage for your dog and recommend additional diagnostics or treatments as needed.
Has your dog taken Metamucil?
Please comment below.
My 1 year old female Labradoodle has had ongoing problems with soft stools and mucus since we moved to a new apartment. I assumed that perhaps it was a change in her environment and change in diet, but after a few months and an huge vet bill ,she still had problems. After doing some research, I came upon your article. I added unflavored Metamucil to a bland diet along with a probiotic. So far, there has been a great improvement after of couple of days since introducing the Metamucil . I’ll continue to keep an eye on her and keep my fingers crossed. Thank you so much for the information.
Hi Priscilla,
I am so glad you are seeing an improvement in your pup! Wishing you continued success and keep up the good work! ♥
Hi there, my dog recently had a bout of diarrhea. The GI upset started on a Sat- he vomited water and then 5 hours later vomited an ice cube. Then diarrhea came Sun-Wed. On Weds we went on metronidazole which stopped the diarrhea and all bowel movements for 5 days. Sunday he pooped finally and he is pooping again (although he skipped Monday, he did poop yesterday) and its not diarrhea or too hard- but its orange and slimy. He is on bland diet since the stomach upset started two Saturdays ago- of chicken and rice and a probiotic powder. Some days I also give 1/2 teaspoon of metamucil. Do you know what are possible causes of orange poop? Could it be normal after a little GI irritation for poop to be orange? We are doing a fecal test but currently waiting for him to want to go again (he is pooping less and not back on his normal once a day poop schedule yet). The vet does not seem worried but I am wondering what the orange poop could mean.
Hi Alyssa,
I am sorry your dog has had so much trouble with his GI tract. I am not sure what is causing his poop to change colors, but it could be the medications or even just the change in his gut bacteria. Hopefully this will resolve as things stabilize and his bowel activity returns to normal. As long as your boy is acting normal, eating and drinking well, and the diarrhea has resolved, I wouldn’t let this change in color be a source of concern. Continue monitoring things at home and keep your vet updated as things progress. Best wishes and keep up the good work!
Our 12 year old mixed breed has suffered with IBS for most of his life. Just recently added a tsp of Metamucil to his food every meal. We were seeing a huge improvement with firmer stools, at least we could pick them up. Got to this weekend and he had a bout of IBS. So he takes Metronidazole to help with the mucous and watery stools. Question I have is while he is taking the Metro, should we continue with the Metamucil?
Hi Nancy,
I am sorry your senior guy is living with IBS. What a blessing the Metamucil has made such an improvement in his bowel movements. I am not aware of any negative interactions between Metamucil and Metronidazole, but it may be wise to give them at different times of the day just to err on the side of caution. Of course, if you have any lingering concerns, don’t hesitate to reach out to your vet for advice. Hoping all is well and that your boy has made a full recovery. Best wishes and good luck!
We have a mixed breed small dog about 14 to 15 pounds mostly terrier and Chihuahua who has had problems with going to the bathroom on a regular. That recommended Metamucil I take it myself after being a colostomy patient years ago and it does keep things regular. I’ve also had a recommendation from a neighborhood Chihuahua owner, who gives his girl, a tablespoon a teaspoon or more of sweet potato once a week that keeps her regular has good fiber great antioxidants and is more natural. We’ve done a mix of both often on half a Metamucil wafer three times a week, sweet potato, one day a week mixed in with her food seems to be doing a wonderful job.
Hi CJ,
I am glad your girl is doing well with the Metamucil and sweet potato. I have also had great success with pumpkin! Thank you for sharing your experience with us. Best wishes to you both and keep up the great work.
My dog is 14.5 lbs and my vet recommended adding 1 tablespoon of Metamucil to his food because of anal gland issues. After reading several articles that seemed like a lot, but I called the vet back and she said no one tablespoon. What are your thoughts?
Hi Lisa,
I understand your concern for your pup. Your vet is probably using their hard-earned experience and knowledge when deciding on a dosage to recommend for your pup. This dosage seems like the standard of care, and I would have no issue with proceeding as directed. Hoping it will have the desired effects you are wanting for your boy. Wishing you both the best of luck!
My vet just recommended Metamucil for my 3 year old golden retriever who has chronic loose stools. After just reading an article about Bloat (yikes). I read yours.
My question: Can Metamucil cause Bloat? My guy isn’t a big water drinker, so now I’m a bit worried. I will of course discuss this with my vet as well. Thank you.
Hi Julie,
I understand your concern for your Golden and hope the Metamucil will help to resolve your pup’s chronic diarrhea. I am not aware of any instances of Metamucil causing bloat, although I cannot make any guarantees. I did do a quick search of the literature to make sure I was not missing something important and did not find any mention of this as a complication. I am glad you are planning to discuss this with your vet. I would be interested to know what they had to say. Feel free to leave an update if you have a chance. Best wishes and good luck!
My Berner has had diarrhea for his whole life (He’s 3.5). After extensive testing and trying every food on the market, we landed on Hills zd. It yields one fairly firm bm a day but there are often 2 or more total diarrhea episodes most days (he wakes us regularly to go out at night too). Just purchased psyllium husk organic to try. I’m supplementing his diet with a probiotic and a small amt of brown rice daily. Question; should I keep giving the probiotic and rice and should I start with 2 tblsps (he weighs 96) or work up to 2? And, should the whole amt be given at one meal?
Hi Nikkii,
I am sorry your big guy is dealing with chronic diarrhea. I think probiotics are wonderful and would not recommend you discontinue it unless your veterinarian instructs you to do so. As for the starting dose of Metamucil, that would be best answered by your vet. Without playing a personal role in your dog’s medical care it is hard for me to make dosage recommendations. Hoping you will start to see the desired results quickly and wishing you the best of luck!
Psyllium fiber seems great for all the benefits it gives dogs. But I’m still conflicted on using it after reading the lead exposure. I have done a lot of research on it and a lot of products are know to fail testing due to high levels of lead, but it’s still sold for human and pet consumption. My major concern is i would need to use this everyday for his bile acid vomiting, empty tummy. Why is that no one seems concerned in the veterinary world. Can I cause my dog to have lead toxicity with chronic use of this product? Please advise, worried dog momma.
Hi Denise,
I was not aware of concerns about high levels of lead in Psyllium supplements until you brought up this important topic. I tried to research this further and cannot find much definitive information that seems trustworthy. I have used psyllium products with many patients over the years and have never had an issue with lead toxicity or exposure. Ultimately, I think it comes down to what you are comfortable with. If you want to avoid psyllium, then talk to your vet to see if they can recommend an alternative. Wishing you all the best and thanks for sharing!
My nine year old German Shepherd/Husky is often constipated. He also suffers from chronic anal inflammation so the constipation can be painful. He gets olive oil daily and pumpkin purée every couple of days but those don’t seem to help. I’m going to try the Metamucil for a few days. Hoping it helps. Thank you for the information.
Hi Carole,
I am sorry your senior guy is having so many GI issues. I hope the Metamucil will help and be just the thing to get him on the right track. Best of luck!
I appreciate all the hard work that goes into your articles! This article was a new learning experience for me! I keep your articles handy for if and when! Thank you!!
Hi Doro,
Thank you for the kind words and positive feedback! Best wishes!
It is uncanny how you send out articles that coincide with what I am going through with my sweet pup. This isn’t the first time! I started giving her Metamucil just this week. Actually, the pharmacy I went to, had a product that was ONLY psyllium husk powder, so I went with that to avoid any unnecessary ingredients. We are only on day 3, but I THINK I see an improvement. I don’t want to get my hopes up too soon. I am trying to firm up loose stools in my 14 year old girl. Thank you for the advice about taking with other meds. My vet didn’t mention that and my girl takes an antacid daily, so I will now give it to her at a different time. Thanks too for all the wonderful articles you provide. Your website is a wonderful resource for all of us fur mamas of senior dogs.
Hi Jenny,
Thank you for the positive feedback about the article. I am glad it was helpful and informative. I hope the psyllium will be the magic fix your sweet girl needs. Best wishes to you both!
Could the prescription food WD or EN also interfere with medication absorption? We give about 1/4 cup of either with 1 1/4 cup dry food and usually put his gabapentin in with his food, but maybe we should not??
Hi Kathy,
I am not aware of any issues associated with medication absorption and these prescription foods. Just to be sure, please bring this up with your vet. They can always contact the manufacturer and get confirmation on these details.