Before I examine a cat, I usually ask the owner if the cat has any problems with coughing, sneezing, vomiting or diarrhea. Even though the cat will vomit hairballs, most people will answer ‘no’ because they think vomiting up a wad of hair is normal. But is it? Probably not based on observations of wild felines who consume hair from their prey as well as grooming, yet do not vomit hairballs.
Although it is still a controversial subject among us veterinarians, I believe that hairballs or trichobezoars are a sign of poor intestinal motility. Instead of passing through the gastrointestinal tract, the hair sits in the stomach growing bigger and bigger until the cat finally vomits. In my experience, vomiting hairballs is often an early sign of a inflammatory bowel disease. Inflammation interferes with normal peristalsis which is why hair accumulates in the stomach. If a cat is vomiting up hairballs on a regular basis, further diagnostics are recommended to rule out inflammatory bowel disease, intestinal lymphoma and other conditions.
For many years, flavored petroleum jelly was the basis of therapy. A one to two inch strip was feed to the cat in order to help the hair pass more easily by lubricating their insides. When prescription diets hit the veterinary market, it wasn’t too long before diets formulated to prevent hairballs appeared. Most are formulated with increased levels of fiber to raise motility. Unfortunately, the fiber blends are often proprietary so it is hard to know if the fiber is soluble or insoluble. Soluble fiber is digested by microbes living in the gut while insoluble fiber passes through unchanged. Neither one of these specifically treat inflammation within the gastrointestinal tract.
To decrease inflammation in the intestinal tract, I recommend a novel, limited antigen canned diet. Since cats are strict carnivores, they do not metabolize carbohydrates as well as humans or even dogs do. Feeding a canned diet dramatically reduces the carbohydrate load as long as it does not contain gravy. In my experience, the frequency of hairballs will slowly decrease over time.