The plasma concentration of ropinirole at different time intervals was subjected to PK analysis to calculate various param- eters: maximum plasma concentration (Cmax), time to reach maximum concentration (Tmax), and area under the plasma concentration–time curve (AUC0→t and AUC0→∞). The values of Cmax and Tmax were read directly from the arithmetic plot of time vs plasma concentration of ropinirole (Fig. 5). The AUC was calcu- lated by using the trapezoidal method (Table 2, Fig. 5). The relative bioavailability (F) of ropinirole after the transdermal administra- tion versus the oral administration was calculated as follows