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Whether you can give Miralax for dog constipation is an important question. 

When your dog is constipated, you may be desperately looking for some remedies to help your dog get relief and you may be wondering whether Miralax for dog constipation may work. 

Before trying to give your dog an over-the-counter product such as Miralax, it's important to first determine the underlying cause of constipation in your dog.

Constipation in dogs is not something that happens very often, and owners at times confuse a dog who is straining to urinate or a dog straining from diarrhea for constipation, with the end result of making matters much, much worse!

 So read on before giving your dog a product like Miralax for dog constipation.

What is Miralax and How Does it Work?

Miralax is an over-the-counter stimulant laxative meant to relieve constipation. It is labeled for human use and also known as "Polyethylene glycol 3350." 

 This drug works by stimulating the nerves in the colon, causing muscle contractions that propel the stool through the colon.

 Miralax also has an "osmotic effect," meaning that it increases the amount of water in the stool, making the stool softer to pass.

Miralax has been used in humans to empty the intestines prior to diagnostic procedures such as colonoscopies, however, it is also used as a short-term solution for constipation.

 It is sold pre-measured 17 gram packets or in  powder form that can be easily stirred into hot or cold beverages. 

First, Is My Dog Really Constipated?

Constipation is defined as infrequent defecation characterized by the passage of small amounts of dry and crumbled feces. A constipated dog is likely to strain and exhibit signs of pain when defecating.

As mentioned, what looks like constipation doesn't necessarily mean you are dealing with a dog who is having a hard time having a bowel movement!

If your are assuming your dog is constipated because you have seen him repeatedly position himself as to have a bowel movement and nothing came out, you may need to take a closer look at what is really happening.

Is Your Dog Straining to Urinate or to Defecate?

If your dog is straining to urinate rather than defecate, then this form of straining is a common symptom of a urinary tract infection. Female dogs are particularly prone to these. 

Suspect a urinary tract infection if your dog is straining and urinating small droplets of urine frequently

Dogs with a urinary tract infection will also have accidents around the house, there may be blood in their urine and they will often lick their private area as it burns.

Orange poop in dog, all rights reserved

Check your yard for signs of diarrhea so to rule out "tenesmus."

Is Your Dog Straining Due to Tenesmus?

In addition to differentiating a dog that is straining to defecate from one that is straining to urinate, you also need to distinguish a dog who is straining to defecate from a dog who is straining because he is suffering from a bout of colitis. 

A dog with colitis has an inflamed colon and will often have soft slimy stools and diarrhea with mucus, and possibly, a droplet or two of blood.

Additionally, dogs with colitis often develop tenesmus, which is the urge to have to frequently empty the bowels, often only producing a drop of diarrhea or nothing at all. 

So if you weren't aware of the fact your dog had diarrhea recently and you just saw him straining, you may assume he's constipated while instead, the problem is quite the total opposite!

In this case, you need to turn into an investigator. Check your yard for fresh messy poops or watch your dog to see if he is straining and pooping a few drops of liquid poop or blood.

If you have noticed your dog recently producing stools, it's therefore likely not a case of constipation you're dealing with, but a case of colitis, points out veterinarian Dr. Andy.

"If you are trying to relieve constipation be careful. Straining to defecate can also be caused by colitis. So, if there has been any recent diarrhea, mucous, or blood in the stool, giving something like Miralax will make it far worse."~ Dr. Andy

Dealing with True Constipation

Constipation in dogs is not really common as it is in humans. When a dog is constipated, it's more likely because of some significant underlying cause. Here are some possible causes of constipation in dogs. 

Intestinal blockages: according to a study, the most common constipation cause in dogs is the ingestion of a foreign body – a life-threatening condition that warrants urgent veterinary help

Low-Quality Diets: more precisely, a lack of fiber from low-quality foods and excess calcium from bones (a main cause of white poop in dogs with a sand-like consistency).

Lack of Exercise – as it happens in people, physical activity is critical for normal bowel movement in dogs, meaning that dogs lacking exercise are at high risk of becoming constipated.

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Inadequate Water Intake – basically what happens is that, the intestines need water to modify the consistency of the feces before they enter the colon, so reduced water leads to dry, hard to pass stools.

Arthritis & Injuries – when a dog presents with inflamed joints and painful conditions of the pelvis, back, and hind legs, they struggle getting into the pooping position. This combined with lack of exercise is a common cause of constipation in old dogs.

 Stress and Anxiety – these are widespread issues in modern dogs and usually manifest with digestive upsets, either diarrhea or the total opposite which is constipation. Dogs who are boarded or hospitalized may become constipated due to stress and abrupt change. 

Certain Medications – constipation may occur as a side effect of some narcotic pain medication such as opiods or butorphanol (often given by vets before or after surgery). Even antihistamines and diuretics can potentially cause constipation in dogs.

Physical blockages-There are other constipation causes that mechanically prevent the passage of stools such as blocked anal glands, an enlarged prostate gland, or simply matted fur around the dog's anus.

Dog liquid black poop

True constipation isn't as common in dogs as in humans and the underlying causes may sometimes be serious. 

The Importance of Seeing the Vet

 As seen, what may look like constipation in dogs may turn out being something else, or if it truly is constipation, the underlying cause can be even very serious!

 Because of this, it' always a good idea to see the vet so to find the underlying cause of your dog's constipation before trying anything at home.

 Once the vet has determined you are truly dealing with a case of constipation that is not secondary to any underlying conditions, you can ask your vet whether Miralax for dog constipation may be used.

 Chances are, you vet may want to prescribe you something that is more effective

Can I Give Miralax for Dog Constipation?

Once your veterinarian has diagnosed your dog with a true case of constipation and has ruled out serious underlying causes, you may think of giving Miralax a try.

 Miralax to treat dog constipation can be added to a dog's food and it should soften the stool enough to ease a dog's constipation, generally working after about 24 to 48 hours, explains veterinarian Dr. Dan. 

According to Dr. Debra Primovic, the dosage of Miralax for dogs is as follows:

  • Small dogs – 1/8 to ¼ teaspoon every 12 hours (twice daily)
  • Medium sized dogs – ¼ to ½ teaspoon every 12 hours (twice daily)
  • Large dogs – ½ to ¾ teaspoon every 12 hours (twice daily)

Consult with your vet for the exact dosage instructions as they may vary based on your dog's precise circumstances and weight.

As with all medications, there are certain guidelines to follow though. 

Miralax should not be given at around the same time other medications are given to your dog because it can reduce their absorption.

 If your dog is taking other medications, it's best that they are given two hours apart from each other, point out Dr. Kate Roby and Dr. Lenny Southam, in the book "The Pill Book Guide to Medication for Your Dog and Cat."

Miralax may lead to side effects including lethargy, nausea, vomiting and increased thirst. It should be used short term considering that longer-term use may lead to  electrolyte imbalances or dehydration.

Consult with your vet before giving your dog a human-designed product such as Miralax.

Consult with your vet before giving your dog a human-designed product such as Miralax.

Use Caution and Contact Your Vet!

You should always consult with your vet before giving any over-the-counter products that are meant for humans. 

If your dog has not been able to poop for more than 24 hours or, in addition to constipation, is showing other troublesome symptoms (like vomiting, appetite loss, low water intake, fever), skip trying to give Miralax and schedule an immediate vet visit.

Calling the veterinarian is imperative because some underlying issues are serious. For instance, consider that a drug such as Miralax can cause a ruptured bowel if your dog isn't pooping because he is suffering from an intestinal blockage!

If you want to try more natural approaches to help your constipated dog, you can try getting your dog to drink more and you can also add some plain canned pumpkin (not the pie mix) to his food, but your best bet is to play it safe and see your vet.

Vet -Approved Ways to Prevent Constipation 

If your dog is constipated, consider that an ounce of prevention is worthy a pound of cure. Veterinarian Dr. Ivana shares below several ways you can prevent your dog from getting constipated in the first place. Here are therefore some simple (and natural) yet efficient ways of preventing doggy constipation.

High-Fiber & Low-Residue Diet

Dogs need both soluble and insoluble fiber to stay regular, and fruits and veggies are their best source. Also, invest in high-quality dog food that leaves low residues, thus preventing bulk formations in the intestines.

Probiotic Supplements for Dogs

Regular use of probiotics is an excellent way to support your dog's gut health and prevent constipation issues. For extra efficacy, most probiotic supplements feature added prebiotics and digestive enzymes too.

Constant Drinking Water Access

As mentioned, dehydration is a common cause of constipation. Make sure your dog has always easy access to fresh water. To entice its water appetite, you can add a few drops of chicken/beef broth or tuna juice in the water.

Regular Physical Activity

Keeping your dog active will keep its bowel movements regular. Exercise or simply walking your dog daily and in accordance with its breed and age requirements can help a lot. Even minor changes in the physical activity regimen can help constipation prevention.

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