In other drug/LPS models, there is also a dependence on the temporal relationship between administrations of drug and LPS, and the time interval needed for a maximal hepatotoxic response is different for different drugs (Shaw et al., 2007; Zou et al., 2009b) . This time interval requirement might help to explain the low frequency of IADRs in human patients: i.e., only when the inflammatory episode happens at a certain time during drug therapy would idiosyncratic hepatotoxicity occur.