„Cortisone is a good medication for rabbits.“
„Glucocorticoids should be avoided in rabbits. Even small single doses (administered subcutaneously, orally, ocularly, or auricularly) have not only an immunosuppressive effect but may also be toxic, particularly in rabbits, which are considered corticosteroid-sensitive. The primary toxic effects involve the liver (fat and glycogen accumulation, vacuolization, hydropic degeneration, bile duct proliferation), lymphatic organs (atrophy), adrenal glands, and other organs (gastritis, gastric ulceration). Additionally, studies have shown that rabbits receiving steroids are more susceptible to infections, recover more slowly, and respond less effectively to antibiotics.“
Kraft, W., Emmerich, I. U., & Hein, J. (2012): Dosage Recommendations for Medications in Small Rodents, Rabbits, and Ferrets. Schattauer Verlag.
Even though it is not widely known, rabbits are a corticosteroid-sensitive species and, unlike other small mammals, dogs, or cats, are significantly more sensitive to the administration of steroids such as cortisone. While there are some rabbits that tolerate cortisone well, these are rare exceptions. Rabbits that have received cortisone for an extended period often suffer from organ damage, develop various illnesses due to a weakened immune system after cortisone therapy, and frequently experience conditions that are difficult to treat later on, as most medications become ineffective.
Did you know? Rabbits should not be given cortisone lightly—not even in eye drops or medications like Surolan. Unlike cats, dogs, and humans, rabbits tolerate it poorly. It should only be considered as a last resort for critically ill animals that would otherwise need to be euthanized, for example, in cases of severe allergic reactions or uncontrollable inflammation.
- Joint diseases when no other treatment is effective.
- Acute respiratory issues, for example, due to heart disease or lymphoma/thymoma.
- The use of cortisone for uveitis in rabbits is a subject of controversy among experts.
„Rabbits and Steroids
Steroids in rabbits cause two types of adverse reactions. Corticosteroids cause a severe immune suppression and liver toxicity. Other internal organs can also be affected. This is not a new finding but has been recognized since the middle of the last century.
The rabbit is a corticosteroid-sensitive species. Therefore, even small, one-time doses can cause severe changes in rabbits. A review of these changes was reported by Borgmann and coworkers. Toxicity in rabbits was documented in lymphoid organs, the liver, and the adrenal gland.
Toxicity was caused by ocular administration of steroids. Typical hepatic changes caused by steroid administration in rabbits include lipid deposits, glycogen deposition, vacuolization, and hydropic degeneration. These changes were seen whether steroids were given orally, ocular, or subcutaneously.
The immune system is affected by steroids in a multitude of ways. Atrophy and disappearance of lymphoid tissue of Peyer’s patches is described as well as lymphoid tissue in the spleen.
Studies have directly revealed the severe damage that occurs to the rabbit liver with administration of steroids. Even with low steroid doses, biochemical evidence of hepatic destruction was demonstrated. Bile acid concentration increased remarkably with steroid administration. In this study, liver pathology included marked proliferation of cholangioles and bile ducts with mononuclear cell infiltrates in portal areas. Some of these steroid-treated rabbits also had gastric ulceration and gastritis.
Other studies looked directly at the affects of steroid-induced immunosuppression in rabbits and the rabbit’s ability to fight off infection. Numerous studies have shown that steroid immunosuppression causes a decreased survival in rabbits.
Rabbits administered corticosteroids are used as a model for studying meningitis. The steroids, even given just once, reduce the immune response, allowing better study of the effectiveness of the antibiotic.
Models of knee joint infections and the influence and effectiveness of antibiotics require the use of steroids in rabbits. Once steroids are given, increased destruction of the knee joint occurs and the antibiotics are less effective.
Another model of infection is the rabbit keratitis protocol. One dose of a steroid causes enough suppression that invasive lesions of the cornea and treatment can be thoroughly studied.“
Karen L Rosenthal (2004): Therapeutic contraindications in exotic pets )
E. Cuniculi and Cortisone
Dr. med. vet. Hein is considered a leading EC expert in Germany.
„The long-time use of glucocorticoids over one or more days is now considered obsolete. Glucocorticoids did not lead to any improvement in any of the combinations (antibiotics ± fenbendazole), carry many side effects (liver toxicity in steroid-sensitive rabbits, immunosuppression, wound healing disturbances, hyperglycemia, etc.), and are often fatal in animals with additional infections due to the resulting immunosuppression.“
She refers to the study by Sieg, which compares different treatment methods.
The literature advises against the careless administration of glucocorticoids and recommends their use only under strict indications.
The use of glucocorticoids is also highly controversial in small mammals. It should only be administered under strict indications (e.g., thymoma/lymphoma, autoimmune diseases). Rabbits, in particular, are highly steroid-sensitive. Even a single use, whether systemic or local, can lead to liver toxicity. Other known side effects include atrophy of lymphatic organs and adrenal glands, effects on the gastric mucosa (gastritis, ulcerations), immunosuppression, and impaired wound healing.
FAQ – Career Entry in Small Animal Practice, Enke Verlag in Georg Thieme 2016.
Borgmann AR, Bogle D, Robb CA, McDonald TO: Comparative toxicity of two-dexamethasone derivatives following topical ocular instillation to rabbits II. Systemic histopathological changes. Toxicology 6:77-84, 1976
BVVD (2016): Berufseinstieg Kleintierpraxis, Enke Thieme Verlag
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Sheng FC, Freischlag JA, Backstrom B, Kelly D, Busuttil RW: The effect of dexamethasone in vivo on blood and peritoneal neutrophils (PMN) in rabbits with peritonitis. J Surg Res 43:296-301, 1987
Ahmed A, Jafri H, Lutsar I, et al: Pharmacodynamics of vancomycin for the treatment of experimental penicillin- and cephalosporin-resistant pneumococcal meningitis. Antimicrob Agents Chemother 43:876-881, 1999
Schurman DJ, Johnson BL, Amstutz HC: Knee joint infections with Staphylococcus aureus and Micrococcus species. J Bone Joint Surg 57:40-49, 1975
Fraser–Smith EB, Matthews TR: Effect of ketorolac on Candida albicans ocular infection in rabbits. Arch Ophthalmol 105:264-267, 1987
Gupta PN, Ichhpujani RL, Bhatia R, Arora DR, Chugh TD: Corneal pathogenicity of Candida albicans in dexamethasone administered rabbits. J Commun Dis 15:36-39, 1983
O’Day DM, Head WS, Robinson RD, Yang R, Shetlar D, Wang MX: Contact lens-induced infection: A new model of Candida albicans keratitis. Iovs 40:1607-1611, 1999
