To show that brucellosis may trigger autoimmune hepatitis (AIH), in addition to nonspecific liver involvement and toxic hepatitis, due to a class effect of tetracycline family used for treatment. We present a female patient admitted to our hospital due to partially improved fatigue and elevated liver enzymes following doxycycline and streptomycin usage for brucellosis. Brucellosis is endemic in our country, Turkey. It may involve any organ in the body. Liver is frequently involved. Doxycycline used for treatment occasionally may lead to hepatotoxicity. AIH is a necroinflammatory disease of the liver. Certain drugs (e.g. minocycline), toxins, and viruses (hepatitis B, hepatitis C, EBV, etc.) can trigger AIH. Only one case of AIH probably caused by doxycycline and brucellosis was reported. We discuss the relationship between brucellosis, AIH, and hepatotoxicity of doxycycline. Brucellosis may trigger AIH. (C) 2005 The WJG Press and Elsevier Inc. All rights reserved.