I have a lot of experience with inflammatory bowel disease (IBD). Two of my own dogs developed the condition, and I’ve treated countless others as a veterinarian.
As its name suggests, abnormal inflammation within the gastrointestinal tract is at the heart of IBD. A healthy intestinal tract is very resistant to the potential adverse effects of all the “stuff” (that’s a technical term) that flows through it. When you think about it, it’s quite remarkable that the gut isn’t sickened more often by all that a pet eats. The GI tract’s various defenses work together to let the good stuff in while preventing everything else from wreaking havoc.
Unfortunately, sometimes these systems break down, allowing cells within the wall of the intestine to come in direct contact with what is eaten. The cause is usually unclear — sometimes there’s a genetic basis, other times altered immune reactions, environmental stress, or antigenic stimulation (e.g., food allergies, bacterial overgrowth, metabolic diseases, food intolerance, parasites, etc.) are to blame, but whatever the cause, the result is inflammation. Abnormal inflammation disrupts the functioning of the GI tract, leading to vomiting, diarrhea, weight loss, and/or poor appetite. An individual’s symptoms depend on where the inflammation is located and how severe it is.
Treatment for IBD involves:
- Eliminating the triggers to inflammation. Feeding a dog or cat with IBD a hypoallergenic diet is sometimes all that is necessary to control the disease.
- Using medications to suppress the abnormal immune response when dietary modifications alone are not sufficient. Corticosteroids (e.g., prednisone or prednisolone) are most commonly prescribed. Other immunosuppressants like azathioprine (dogs) or chlorambucil (cats) can be used in severe cases or if corticosteroids cause unacceptable side effects.
A new study hints at a tweak to the corticosteroid option mentioned above. Some pets are very sensitive to the adverse, systemic effects of these drugs. When receiving relatively low doses, they start to drink a lot of water, produce large amounts of urine (sometimes leading to incontinence), pant excessively (dogs), and develop infections, thin skin, muscular weakness, and a pot-bellied appearance. A “perfect” corticosteroid for IBD would reduce inflammation in the GI tract after being swallowed but not be absorbed systemically thereby eliminating these side effects.
While not perfect by any means, the drug budesonide has some of these characteristics. When ingested it almost acts like a topical medication applied to the tissues lining the gastrointestinal tract. Budesonide undergoes extensive first pass metabolism, meaning that what is absorbed goes directly to the liver and is broken down before it enters general circulation.
The study in question only looked at 11 dogs with moderate to severe IBD, but reported that 8 of them had an “adequate” response to budesonide and no adverse effects were reported. Budesonide certainly looks worthy of consideration in dogs (clinical experience also supports its use in cats) that either don’t respond adequately to traditional treatments or develop intolerable side effects from systemic corticosteroids.
Dr. Jennifer Coates
Pietra M, Fracassi F, Diana A, Gazzotti T, Bettini G, Peli A, Morini M, Pagliuca G, Roncada P. Am J Vet Res. 2013 Jan;74(1):78-83.