Diarrhea can be classified as acute or chronic, depending on its duration. Acute diarrhea comes on suddenly and is finished in a short period. Chronic diarrhea often comes on gradually and persists for three weeks or longer, or has an episodic pattern of recurrence.
Chronic diarrhea requires veterinary investigation.
Food in the small intestine takes about 8 hours to reach the colon. During that time, the bulk of the food and 80 percent of the water is absorbed. The colon concentrates the remainder. In the end, a well-formed stool is evacuated.
Transit time in the intestinal tract can be speeded up for a variety of reasons resulting in a large, loose, unformed bowel movement. This accounts for the majority of acute diarrheas of short duration.
To determine the cause of the diarrhea, it’s impoprtant to decide where the disease is located: small intestine or colon. This is done by examining the color, consistency, odor and frequency of the stools, as well as the condition of the dog:
- Yellow or greenish stool — indicates rapid transit (small bowel)
- Black, tarry stool — indicated bleeding in the upper digestive tract
- Bloody stool — red blood or clots indicate bleeding in the colon
- Pasty, light-colored stool — indicates lack of bile (liver disease)
- Large, grey, rancid-smelling stool — indicates inadequate digestion or absorption (malabsorption syndrome).
- Watery stool — indicates small bowel wall irritation (toxins and severe infections)
- Foamy stool — suggests a bacterial infection
- Greasy stool — often with oil on the hair around the anus: indicates malabsorption
- Excessive mucus — a glistening or jellylike appearance; indicates colonic origin.
ODOR (the more watery the stool, the greater the odor)
- Foodlike, or smelling like sour milk — suggests rapid transit and malabsorption: for example, overfeeding, especially in puppies
- Putrid smelling — suggests an intestinal infection.
- Several in an hour, each small, with straining — suggests colitis (inflammation of the large bowel)
- Three or four times a day, each large — suggests a malabsorption or small bowel disorder
CONDITION OF DOG
- Weight loss, malnutrition — suggests small bowel disorder
- Normal appetite, minimal weight loss — suggests large bowel disorder
- Vomiting — small bowel origin, except for colitis
Common Causes of Diarrhea
Intestinal parasites are a common cause of acute and chronic diarrhea in puppies and adults. The greatest problems are caused by roundworms, hookworms, whipworms, threadworms, and giardia.
Most cases are caused by an irritation of the bowel lining from ingested substances or infections agents — in other words, something they ate. Any change in your dog’s diet could be the trigger: unfamiliar water; intolerance to certain foods like beef, pork, chicken, horsemeat, fish, eggs, spices, corn, wheat, soy, gravies, salts, spices, fats, and some commercial dog foods; excitement or emotional upset.
Dogs are scavengers and sometimes tend to eat things they can’t digest like:
- dead animals, rodents and birds
- garbage and decayed food
- rich foods, table scraps, gravies, salts, spices and fats
- sticks, cloth, grass, paper, etc.
- parts of flea collars
Toxic substances causing diarrhea include:
- gasoline, kerosene, oil or coal tar derivatives
- cleaning fluid, refrigerants
- bleaches, often in toilet bowls
- wild or ornamental plants, toadstools
- building materials: cement, lime, paints, caulks
- fireworks containing phosphorus
Many of these are equally as irritating to the stomach and will cause vomiting.
Diarrhea is a symptom. The first step in treating it is to identify and remove the underlying cause, if possible. If the diarrhea is caused by overeating, cut back the food intake and feed 2-3 times a day in controlled portions. If unfamiliar water is the problem, carry an extra supply with you. In the case where irritating or toxic substances have been ingested, an effort should be made to identify the agent as specific antidotes may be required.
Food allergies can be cleared up by removing the problem food. Sometimes changing a dog’s food can trigger diarrhea. The new food should be introduced slowly over a couple weeks to avoid this kind of diarrhea.
Most cases of diarrhea can be treated at home:
- Withhold all food for 24-48 hours. If your dog appears thirsty, give a small amount of water or ice cubes to lick.
- Administer lomotil at a dose of one tablet per 25 lbs of dog, three times a day. Or Kaopectate at 1/2 – 1 tsp per 5 lb, to a maximum of 2 Tbsp every 8 hours. Or Pepto-Bismal at 0.5 ml per lb or 1/2-1 tsp per 5 lb, to a maximum of 30 ml or 2 Tbsp.
- As the dog starts to respond, feed an easily digested diet that contains no fats:
- boiled hamburger (1- to 2-parts cooked rice; discard the broth)
- cottage cheese
- cooked macaroni or soft-boiled aggs
Prescription diets are available from your vet.
- Continue the bland diet for three days, even if your dog seems better.
A diarrhea that persists for more than 24 hours, a bloody diarrhea and diarrhea accompanied by vomiting, fever and other signs of toxicity should be checked out by your vet immediately.