Figure 1. (Upper) Cerebropinal fluid (CSF) neostigmine concentrations over time in volunteers for 6 h after intrathecal injection at time 0 of neostigmine, 50 [micro sign]g (solid thin line), 150 [micro sign]g (dotted line), 500 [micro sign]g (dashed line), or 750 [micro sign]g (solid thick line). (Lower) Unit disposition curves and dose-normalized concentrations of neostigmine in all patients. The thin solid lines are the post hoc Bayesian estimates of the pharmacokinetics, and the thick line represents the population estimate of the pharmacokinetics (Table 1).