ABSTRACT
The number of individuals who develop liver toxicity is very small, even for drugs considered
particularly hepatotoxic. The major reason for this is that intrinsic hepatotoxicity, toxicity that
predictably occurs at a given dose, is most commonly weeded out during preclinical testing if
the toxic dose is close to the therapeutic range (i.e., narrow therapeutic index). Drug overdose is
the major setting for intrinsic hepatotoxicity. The most commonly seen form of drug-induced
liver injury is idiosyncratic hepatotoxicity. By definition, idiosyncratic hepatotoxicity occurs
within the therapeutic dose range, but only in susceptible individuals. This chapter examines
some of the factors that lead to this susceptibility.
