This article explains how I go about discovering the cause of diarrhea in you pet and some of the ways I treat it. Not every cause of diarrhea or medication is covered - but the most important ones are.

Why Is This Happening?

Anything that inflames or irritates the lining of your pet's intestine will cause diarrhea. When your pet's body senses that something is in its intestine that shouldn't be there, it try's to get it out as rapidly as possible. If it is high in your pet's digestive tract it will vomit. If it is lower in the tract it will come out as diarrhea.

How A Veterinarian Finds The Cause Of The Problem:

I am always delighted when a client actually brings me a sample of the mess that their pet made. In more than half the cases, the diagnosis can be made from a fecal specimen and history alone. Try to bring in a fresh specimen – no need for more than a few tablespoons full.

Because my patients can’t talk, the history that you provide is extremely important. The first question I will ask you is whether this is a sudden acute problem or if it is chronic and has been going on quite a while. The next thing I will ask is if you fed something unusual to the pet or if torn remnants of some household object are strewn about the house.

Is This A High Intestinal Problem Or A Low Intestinal Problem ?

First we need to get a general idea as to what part of your pet's intestine is inflamed. Cases of diarrhea fall into two groups in approximately equal numbers. In the first group, the problem is in the small intestine and in the second group in the large intestine, cecum or rectum. High diarrheas tend to be the most dangerous. Sometimes, the problem is a combination of both types.

When the problem is high in the small intestine your pet will eliminate large amounts of stool, but the frequency of its bowl movements is not increased. If there is blood in this stool, it will be chocolate-colored, not bright red. There won't be much straining when the pet defecates. The stool in cases of high diarrhea is not thick, sticky or mucoid. Vomiting may accompany high small intestinal problems.The pet may also have a tummy ache.

The second group of pets have a problem in their large intestine. These pets have frequent, uncomfortable eliminations. When they go, the amount of stool is small and often covered with mucus. They take a long time to poop and try several times. If the colon is inflamed enough, the stool may be coated with flecks of bright red or rust-colored blood. Pets that have eaten bones, sharp or gritty objects often have a mixture of diarrhea and constipation. The material passed is a combination of hard lumps and soft or watery stool. These pets may need laxatives or enemas to clean their system out.

Is This A Primary or Secondary Problem ?

Sometimes the underlying problem is located in the intestine. But sometimes, their is a problem somewhere else in your pet's body that is the root cause.

Along with history, the veterinarian's physical exam and laboratory tests help determine this. In most cases, there are very few abnormal blood work results when the problems is in the intestine itself. In these cases, abnormal physical exam findings are all limited to an inflamed, thicken and painful intestine. With primary intestinal problems I can often feel enlarged lymph nodes that collect lymph from the intestines.

Diarrhea also occurs secondary to problems in other organs of your pet's body. When I am fortunate, blood work panels and a careful physical examination will identify this disease. The Uremia of kidney failure is a common cause of diarrhea in pet. So is liver disease (hepatitis). Addison's Disease, affecting the pet's adrenal gland, as well as an over-active thyroid or hyperthyroidism or medications to treat these and other conditions can also cause diarrhea in your pet. A sudden inflammation of the pancreas or pancreatitis also will cause diarrhea in dogs and cats.

Dehydration:

This is the most serious complication of severe diarrhea. Severe diarrhea is most serious in very young, very old and very small pets. They can become severely dehydrated very quickly. Dehydration in small pets and frail elderly animals can be fatal because their surface area is large in proportion to their body weight. As dehydration progresses these pets have trouble maintaining their body temperature and may lapse into coma. Only the rapid infusion of intravenous fluid will save them.

When the problem is minor, giving fluids such as Pedialyte is sufficient. When the dehydration is severe, the pet needs to be hospitalize and the fluids given by intravenous drip.

Body Temperature:

The body temperature of your dog or cat should be about 101.5 F (38.6C). In some cases of severe diarrhea and dehydration, their temperature will drop below 100 F (37.8C). These pets need to be warmed. In fewer cases, their body temperature will go above 102. 6. F (39 C). These pets need to be cooled - or they need to receive medications to lower their body temperature.

What Complications Might Occur?

Intestinal inflammation in young pets with diarrhea occasionally causes the intestines to thrash about so vigorously that the intestines tie themselves in knots (volvulus) or fold in upon themselves (intussusception). Both these conditions can be life threatening.

What General, Non-Specific Treatment Are Available To Me At Home When This Is A Minor Problem?

Diarrheas in dogs caused by eating the wrong foods or transient stress often improve if you withhold food for 24 hours and give the pet kaopectate 0.5-1.0 ml/pound every four hours.

Some brands of kaopectate were reformulated to contain bismuth subsalicylate in addition to the old ingredients which were attapulgite and alumina clay. Dogs can handle this compound well, but if too large a dose is given to cats it can be toxic.

loperamide (0.2mg/ml Imodium, Equate Liquid WalMart) at 1ml per four pounds two or three times a day or in tablet form at 0.05-0.1 mg/pound every 8 hours). DO NOT EVER GIVE IMODIUM TO CATS!

If you give give your dog too much Imodium, you will make him constipated.

Serious cases of diarrhea begin exactly the same as non-serrious cases of diarrhea and only your veterinarian is qualified to tell one from the other.

Diarrhea that contain blood, persists more than 24 hours or affect your pet's general activity and perkiness needs the immediate attention of a veterinarian. So does diarrhea that rapidly dehydrates your pet. When you visit your veterinarian, be sure to bring along several tablespoons full of the pet's stool in a sealed baggie. I know this is an unpleasant task. But I often find the cause of the problem right away by passing the stool through a sieve or examining it under a microscope. You veterinarian may be able to obtain a stool specimen directly from your pet but it might not be enough for all the examinations that should be done. Wash your hands well - because some of the infectious causes of diarrhea can affect you too.

Checking The Stool Specimen:

This is the fun part about being a veterinarian – poking through poop. Depending on the history you give about your pet's life style, I often pass the material through a strainer to hunt for objects such as leaves, sticks, glass, or aluminum foil that are the source of the problem. I have found every imaginable thing.

Then I prepare slides of the material to examine under my microscope. Some of these cases show a normal digestive process where food is being digested and absorbed. In others, fat globules are present and protein particles are sharp – evidence of poor digestion. These cases are either maldigestion or malabsorption. They can be due to a hyper-motile intestine or the lack of normal liver and pancreatic enzymes. Some stool is abnormally light in color due to a lack of these enzymes. This is a hint of liver, pancreatic or gall bladder disease. Many times, I find things like bug parts that allow me to diagnose the problem without further tests. Other times common intestinal parasites or their eggs are visible under the microscope.

What Are Some Common Causes Of Diarrhea?

Diarrhea Caused By Pet Care:

Pet Food Quality
Buying that marked-down, generic brand of dog or cat chow instead of your regular name brand is very common cause of diarrhea. Actually, any time you switch brands of food, a period of diarrhea is apt to occur. Quality costs money - when you go below a certain price, the quality of the ingredients suffer. “High Protein” means very little. Feathers, hooves and beaks are all protein. But they are not digestible protein and they will cause diarrhea. Try to select a medium-priced pet food -. neither the cheapest nor the most expensive. And always stay with the same brand. Little companies that market their products through specialty stores have a hard time screening their ingredients or producing a product that does not vary from batch to batch. So feed a diet produced by a large company that makes other products that you trusts - not one sold by the groomer or seen on the internet.

Overeating
Some dogs and many cats over-eat when they are fed once a day. This can result in diarrhea, colic and vomiting. I suggest feeding dogs and cat with this problem three times a day or leaving the food where they can munch whenever they please. Just don't let them become overweight.

Foods That Don’t Agree With Pet
Some pets are intolerant to certain ingredients in pet foods. This can be beef, liver or chicken, preservatives, dyes and the like. Very few pets are actually allergic to pet food ingredients. You can try a diet made with different ingredients or you can make your own at home.

Stress
Some pets – toy dogs, nervous cats and ferrets in particular – vent stress through their intestines. This can take the form of vomiting, refusal to eat, diarrhea or blood in the stool. After this occurs several times, owners usually draw the connection between events that upset the pet and bouts of diarrhea. These pets should be checked to be sure they are not suffering from Addison's Disease .

Dietary Indiscretions
The most common cause of diarrhea in dogs and ferrets (not so much in cats) is dietary indiscretions – the eating of garbage, grass, plant leaves, etc.

It is amazing the things pets will eat ! Many of these cases are actually separation anxiety cases where a panicky pet eats everything in sight . Placing these pets on a large dose of petrolatum-based cat laxative may help slide this material out with the stool. These pets need to be monitored carefully for seventy-two hours to be sure the intestine does not block. And they need to be confined in an area that can be easily cleaned up. I sometimes feed them art glitter and wait for it to come out the other end. At the first sign of abdominal distress, depression, general weakness, fever or blood in vomitus or stool, they should be rushed to a veterinarian for further testing. They also need immediate veterinary care if you suspect that they ate something dangerous or sharp.

Diarrhea Caused By Medications And Chemicals:

Antibiotics And Sulfonamides
Many antibiotics and sulfas kill the normal, helpful bacteria in the pet's intestine as well as the dangerous ones. When the normal bacterial flora of the intestine is destroyed diarrhea may result. This problem can occur with injected antibiotics as well as oral ones. Giving the pet yogurt or bacterial gel pastes, decreasing the antibiotic dose, or changing to a different antibiotic might all help. Do not do this without a veterinarian's permission.

Other Drugs From The Pharmacy
Many medications that we dispense to your pet can cause diarrhea. Thyroid medication, NSAI drugs such as Rimadyl and aspirin, worming medications, and topical insecticides are only a few of the many medications that can cause diarrhea. Some pets are just sensitive to a particular medication. Some pets do better when less of the medication is given or when less is given - but in more frequent doses.

Diarrhea Caused By Parasites :

Intestinal Worms:

Hookworms, roundworms, whipworms and strongyloides are some of the nematode parasites that cause diarrhea in dogs and cats. These organisms are the most common causes of diarrhea in puppies and kittens. They are also threat to children who are accidentally exposed to your pet's stool. You can read about these parasites and how I deal with them in other articles on my web site. If their are enough parasites to cause diarrhea, their eggs are usually seen when the stool is examined with a microscope.

Protozoan Parasites:

Some protozoal parasites are single-celled microscopic parasites of the intestine. Diarrhea is their primary sign. This group includes coccidia and giardia. We treat them with bland diets, sulfonamides and metronidazole. Giardia can cause similar problems in pet owners – particularly children.

Diarrhea Caused By Viral Infections:

Parvovirus Of Dogs
Parvovirus infection of dogs causes severe foul-smelling diarrhea. Mature dogs recover after a period of diarrhea but the disease is often fatal in young unvaccinated pups or very small breeds. Parvovirus attacks the lining of the small intestine causing bloody diarrhea and vomiting. Dogs are severely depressed, dehydrated and in much pain. These pets die from fluid loss and shock, so most of my efforts aim at replacing these fluids. Parvo-infected dogs cannot keep oral fluids and medicines down so I give our fluids and medications by injection. vaccinate puppies against.

Coronavirus Of Cats
Feline enteric Coronavirus is highly contagious among cats but rarely fatal. The virus is shed in the feces of carrier cats causing erosion of the lining of the intestine. Recently weaned kitten have fever, vomiting and diarrhea that lasts 2-5 days. They loose their appetite. I treat them with fluids, antibiotics and medications to slow the diarrhea.

Diarrhea Caused By Bacterial Infections:

Spoiled Food – Food Poisoning
Spoiled food is often contaminated with toxins and bacteria that cause pets to have diarrhea and vomit. Food poisoning usually resolves itself after the contaminated material is purged from the body. It is unwise to give these pets medications that prevent diarrhea and vomiting because this traps harmful bacteria and toxins within the body. Two common bacteria involved in these cases are Staphylococcus and Escherishia coli (E. coli). Dehydration is the most serious side effect of diarrhea and vomiting. Infant animals can quickly go into shock from dehydration. Products such as Gatorade or Pedialyte are excellent for preventing this. If the pet can't hold liquids down, the fluids must be given intravenously or subcutaneously by a veterinarian.

Salmonella And Campylobacter In Dogs And Cats
Feeding poorly cooked meat products and chicken pass these bacteria to pets and humans. As with food poisonings, keeping the pet well hydrated is extremely important. In catteries, adult cats carrying salmonella often pass it to their kittens with sometimes fatal results. I have found it very difficult to get Salmonella out of a group of cats once it has become established. Batryl (enrofloxacin) is an excellent drug to use in adult pets with diarrhea but it cannot be used in growing animals. This is my chief concern in feeding RAW diets to your pets. I do not recommend them.

Diarrhea In Cats Caused By Bartonella:

An organism call Bartonella has been implicated in chronic gastrointestinal infections in cats and occasionally dogs. Until recently, Bartonella was primarily associated with Cat Scratch Fever. The diagnosis of Bartonella infection is made using a laboratory tests . When cats or dogs are positive for this organism it can be successfully treated using azithromycin, doxycycline or rifampin.

Acute Gastroenteritis of Ferrets
Several bacteria cause infections of the gastrointestinal tract of ferrets that appear as bloody diarrhea, vomiting and dehydration. Stress is often the precipitating factor in these conditions. Ferrets that vomit and pass fluid stools rapidly dehydrate. Dehydration can be fatal in these pets. The first thing I do is give the ferrets large doses of intravenous and subcutaneous fluid. (5% dextrose). I place them on injectable antibiotics, keep them warm and withhold all food and oral liquids. Bacteria most often associated with this problem are salmonella, helicobacter and campylobacter. Because diarrhea and vomission remove these bacteria and their toxins from the body I rarely attempt to lessen them. Instead, I replace the fluids and nutrients, as they are lost.

Poorly Understood Causes (Idiopathic):\

Inflammatory Bowel Disease (IBD)

eDogs and cats sometimes develop intestinal inflammations, diarrhea and vomitting for causes that are not always clear. For more information on Inflammatory Bowel Disease in your dog, go here. For more information on Inflammatory Bowel Disease in your cat, go here.

Hemorrhagic Gastroenteritis Of Dogs
Toy breeds of dogs are susceptible to bloody diarrhea the cause of which remains unknown. No doubt many of these cases fall into other groups I have mentioned but were not diagnosed. Many of these cases are due to stress. Some emotional dogs exhibit stress through their intestines. In other dogs, the problem is probably undiagnosed Addison's disease in which the body is deficient in cortisone. Most of these cases respond well to IV fluids, food deprivation for 24-48 hours and then a gradual increasing amounts of bland diet fed. I give most of these cases the oral corticosteroids, prednisolone or prednisone and place many of them on the sulfonamide, Tylocin. These problems tend to reoccur in the pet from time to time. If they reoccur , the root cause needs to be discovered.

Eosinophilic Enteritis Of Cats

This is a portion of eosinophilic complex of cats. It shares a lot of characteristics with inflammatory bowel disease of cats (IBD). Read more about IBD of cats here .The signs are diarrhea, weight loss and vomiting. We suspect the problem is a food allergy. Cats with this problem often have elevated numbers of white blood cells called eosinophils. These cells are associated with allergic conditions in pets and people. Sometimes the skin is ulcerated as well or ulcers are present on the lips tongue and mouth. The disease responds to injections and oral forms of corticosteroids such as methylprednisolone acetate. It also often responds to the human birth control medication, Depopovera (medroxyprogesterone acetate). Moving the cat to a different home or environment and feeding bland diets also help bring the disease into remission. I have also seen the skin and oral form of this disease disappear when fleas were eliminated from cats.

Inflammatory Bowel Disease of Ferrets

In this condition the lining of the stomach and small intestine becomes inflamed and may also ulcerate. Some feel that this condition is a form of autoimmune disease - others that it is due to allergies to various ingredients in ferret diets (possibly chicken). Perhaps both can play a part. Ferrets with this condition pass frequent loose watery stools and may also vomit. They become very thin. Diagnosis of this condition is often made by elimination of other causes. Exact diagnosis can only be made from biopsies of the pet’s intestine, which may require surgery. Because the symptoms are quite similar to acute and chronic bacterial gastroenteritis of ferrets, stool samples need to be cultured for these bacteria. When these causes of similar disease have been eliminated, the ferrets usually improve on a regimen of amoxicillin, metronidazole (Flagyl) and prednisolone. This disease is rarely cured but it can be managed. I usually also put these pets on Pepto-Bismol and Tagamet. It is hard to put weight on them because food moves too rapidly through their intestines and much of the absorptive power of the intestinal lining has been lost. This is why additional vitamins help these pets.

During flare-ups, liquid diets such as AD can be feed. Then, feeding one of the bland diets marketed for similar conditions in dogs and cats (i/d, EN, ZD, etc.) often minimizes this problem. Bland diets marked for cats have sufficient protein but those manufactured for dogs contain less than the optimal amount for ferrets. If dog products are used, I suggest that they be supplemented with vitamins, cooked egg whites and cottage cheese. Low intermittent oral doses of corticosteroids such as prednisone are also helpful.

Lymphangiectasia Of Dogs

Sometimes called plasmacytic enteritis, this condition is diagnosed by a pathologist’s examination of snippets of the wall of the small intestine which are removed at surgery. Lymphangiectasia is an improperly formed intestinal lymphatic system, which results in protein being lost from the body (protein-loosing enteropathy). We think that in some cases the pets were born with this disease and in others they acquired it later in life. Most affected pets respond to a combination of bland diet and anti-inflammatory doses of corticosteroid drugs such as dexamethasone or prednisolone but the disease is never cured. Diets you prepared should contain minimal fat with ample amounts of high-quality protein.