Senior pets can develop diarrhea for a variety of reasons, from eating something that causes gastrointestinal (GI) upset, to a systemic disease. Consider whether one of these causes may be to blame.

If your senior pet has been whining urgently to go outside more than normal, or worse, soiling your floors, you may wonder what is causing their more frequent, soft bowel movements. Senior pets can develop diarrhea for a variety of reasons, from eating something that causes gastrointestinal (GI) upset, to a systemic disease. A veterinary visit is warranted any time your pet has diarrhea for more than 24 hours, since debilitating dehydration and electrolyte loss can result. In the meantime, consider whether one of these causes may be to blame.

#1: GI sensitivity in senior pets

As your pet ages, their GI tract becomes more sensitive, and is more likely to object if your pet eats something out of the ordinary. Common offenders include:

* Rich human foods

* Table scraps

* Leftovers stolen from the trash

* Treats containing artificial flavorings, such as flavored rawhides

* Bones, hooves, or antlers

Also, consider whether you have changed your senior pet’s diet, or given them a new treat that may have upset their sensitive GI tract.

#2: GI parasites in senior pets

Many pet owners assume their older pets no longer require regular preventive care, such as vaccines and parasite prevention. On the contrary, however, senior pets often have weaker immune systems, and cannot easily fight off foreign invaders. Your senior pet can pick up a variety of GI parasites, including Giardia, coccidia, and intestinal worms, that can cause diarrhea. 

#3: Medications and senior pets

Medications can cause a variety of side effects, including diarrhea. Antibiotics, in particular, can kill off beneficial bacteria in your pet’s intestines, allowing other bacterial species to overgrow and disrupt the normal balance. A new medication may be to blame for your pet’s increased potty breaks.

#4: Stress in senior pets

Senior pets, particularly those with cognitive dysfunction, are prone to higher stress and anxiety levels. Any change in your pet’s normal routine, including household changes, a trip to the groomer, or a boarding facility stay, can stress your pet and trigger a bout of diarrhea. Try to keep your senior pet’s routine constant and low-key to minimize stress and anxiety.

#5: Dietary changes in senior pets

Your senior pet’s GI tract digests the same food day after day, and produces the enzymes needed to break down the specific ingredients. If you suddenly change your pet’s diet, their system will be unprepared to digest the new ingredients, most of which will pass through without being absorbed, which can lead to diarrhea. Make any changes to your senior pet’s diet by gradually mixing the old and new foods. Start with 25% of the new diet and 75% of the old diet, and slowly increase the ratio over 7 to 10 days. This will give your pet’s GI tract time to get used to the new food ingredients and produce the appropriate enzymes.

#6: Bacterial imbalance in senior pets

Each pet has a delicate balance of bacterial species living in their GI tract that aid in digestion. Almost anything that incites diarrhea, including antibiotic use and parasitic infections, can upset this balance, and prolong diarrhea. In other words, diarrhea may persist despite the primary problem being resolved, because of the residual bacterial imbalance. In this case, probiotics can help restore your pet’s GI flora by repopulating their intestines with beneficial bacteria.

#7: Enzyme deficiency  in senior pets

Exocrine pancreatic insufficiency (EPI) develops when the pancreas no longer produces sufficient digestive enzymes, and a pet’s food passes through their GI tract without being adequately broken down. EPI can develop after severe pancreatitis leaves your pet’s pancreas scarred, or for unknown reasons. Although pancreatic function cannot be restored, enzyme supplements can help your pet better digest their food.

#8: Systemic disease in senior pets

Your pet’s different body systems are complexly intertwined, and a disease that affects one system often has far-reaching effects. Several systemic diseases can cause diarrhea, including:

* Kidney failure

* Liver disease

* Gallbladder problems

* Irritable bowel disease

* Addison’s disease

* Cancer

Your family veterinarian will perform a thorough physical exam and diagnostics, such as a fecal analysis and blood work, to get to the bottom of your senior pet’s diarrhea.

If your senior pet has chronic diarrhea, or another ailment that impacts their quality of life, you may need help supporting them during their last weeks and months. Our telehospice service can help you assess your pet’s quality of life, and establish veterinary hospice care if necessary.