Concentration of Compounds by Transporters

TABLE 5.6 On- and Off-Target Interactions for a Promiscuous Drug Trifluoperazine (Log P 5, TPSA 9.7A ) as Defined by Price et al. (2009) 

These were defined as multiple receptor interactions above 10 pM and toxicity effects above 1 pM unbound drug. 

Other groups (Azzaoi et al., 2007 Peters et al., 2009) have conducted similar in vitro assessments of promiscuity and selectivity and reached similar conclusions to the Price study that increased lipophilicity and lower PSA decrease selectivity and increase promiscuity. 

Metabolites may be responsible for or may contribute to the toxicity of a drug molecule. Metabolites may be unstable and chemically reactive. In these instances toxicity may be 

High local concentrations of free drug at the on- or-off target proteins may occur due to the transport of a drug molecule (or metabolite). In almost all cases such drugs have defined physicochemical characteristics. In contrast to the compounds described in the section on basicity, lipophilicity, and volume of distribution as predictors of toxicity, the likelihood 

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