Hairballs (Trichobezoars) in Rabbits

For rabbit owners, the word hairball can strike fear in their hearts. Hairballs have long been considered one of the most serious ailments, with the potential to cause death. But what exactly is a hairball and why does it seem to primarily affect pet rabbits and not their wild cousins?

A hairball, technically called a trichobezoar, is an accumulation of hair within the digestive tract. It is thought that this hair is ingested when the bunny grooms. The accumulated hair bunches up into a ball that cannot pass through the intestinal tract, usually leading to an obstruction. This is also referred to as wool block, gastric stasis or hair block. The stomach is the most common part of the intestinal tract affected. Cats are also commonly affected with hairballs, but the difference between cats and rabbits is that cats typically and harmlessly vomit their hairballs. Rabbits do not have the physical ability to vomit.

Historically, rabbits with poor appetite, smaller fecal pellets, weakness and weight loss are often diagnosed with a hairball obstruction. Sometimes, X-rays are taken to evaluate the intestinal tract. Without treatment, many of these bunnies do not survive.

Treatment of hairball obstructions can be either medical or surgical. Medical treatment includes the administration of injectable fluids, most often subcutaneous, and medication to try to increase contractions of the intestinal tract. If not effective, surgical removal of the hairball may be necessary.

Prevention of hairballs has been an important part of keeping your rabbit healthy. Prevention usually consists of daily grooming, cat hairball medication, pineapple juice or papaya enzyme. It is theorized that these fruits have an enzyme that helps breakdown hair. Unfortunately, this has not been scientifically proven.

For years, veterinarians have noticed that after removal of the hairball from the affected rabbit, the hairball readily fell apart in a small amount of water. They began to wonder why hairballs weren't falling apart in the liquid of the stomach and why it was causing a problem. They also wondered why hairballs did not cause serious and common illness in wild rabbits.

After years of research, the syndrome of hairballs is being reevaluated. The most current thoughts are that the real culprit is not hairballs; it is abnormal gastrointestinal function.

Gastrointestinal Problems

Most rabbits afflicted with hair balls are on a high carbohydrate, low fiber diet. These rabbits are most often kept caged and have been under stress, causing changes in the motility and function of the stomach and intestines.

What these new thoughts mean to the pet rabbit is primarily aimed at preventing problems. Treating a rabbit with a suspected hairball or intestinal motility problem remains the same. Initially, injectable subcutaneous fluids and motility stimulating drugs are used and the rabbit is force fed. Most rabbits respond to this treatment in about four to five days. If there is no response to treatment, surgery is needed in an attempt to save the pet.


Preventing hairballs is crucial to maintaining the health of your rabbit. It is thought that hairballs are a secondary problem. The real problem is a motility problem. By keeping your bunny healthy, hairballs are often prevented.

High fiber diets have been found to reduce the incidence of hairballs drastically. This means that your rabbit should have plenty of fresh timothy or oat grass hay available at all times and plenty of fresh greens available.

Offer limited pellets. This diet provides sufficient moisture and fiber to keep your rabbits internal organs functioning in top form. Continuing to groom your rabbit and even providing pineapple or papaya can still be helpful. Even if these have not been proven to prevent hairballs, at least they don't do any harm.