An 8 year old spayed female Jack Russell Terrier presented for evaluation of previously diagnosed chronic hepatitis. Physical exam revealed jaundice, hepatomegaly, petechiae, and ecchymoses. Bloodwork showed severely increased liver enzymes, prolonged clotting times, and decreased coagulation inhibitory proteins. ELISA and Western blot were strongly positive for Borrelia infection. A liver Tru-cut biopsy revealed lobular dissecting hepatitis, but stains were negative for the Borrelia organism. Differentials included primary immune-mediated hepatitis, or immune-mediated hepatitis secondary to Borrelia, which has never been documented in the dog. Medical management included doxycycline, dexamethasone, azathioprine, ursodiol, SAMe, vitamin E, plasma, vitamin K, aspirin, and famotidine. The dog responded well to medical therapy with normalization of her liver enzymes and improvement in general attitude over the following months. This paper will discuss each of these medical therapies in more detail.