Figure 3

Determining the prescribed tolerance. Difference between a prescribed tolerance of (A) 0.1 μM and (B) 0.01 μM for the reverse transcriptase inhibitor Didanosine (ddI). The red line plotted on both graphs is the average drug concentration while taking drug holidays. This was calculated using the data from Table 2. The average drug concentration in (A) is around 11 μM and has not reached the trough values when drug holidays are excluded, whereas the average drug concentration in (B) is around 12 μM and thus exceeds the trough values during therapy.