A calculator program for individualizing factor VIII dosage.
We developed a calculator program to individualize Factor VIII dosage on the basis of the concentration-time data obtained after a single test-dose. The program is designed for the Hewlett-Packard 41-CV calculator. The calculation procedure is the 1977 version of the Sawchuk and Zaske method. The program performs model parameter estimation through a nonlinear iterative least-squares technique (the modified Gauss-Newton method). We tested our program in three patients with classic hemophilia who required multiple-dose treatment with Factor VIII. In each patient, individual kinetic parameters were estimated from the serial plasma levels measured after the test-dose. The predicted concentration-time curve resulting from all the administered doses was calculated based on the estimated kinetic parameters. Good agreement between predicted and measured levels during the multiple-dose regimen was observed in all patients.
D003201:Computers; D004334:Drug Administration Schedule; D005169:Factor VIII / Q000008:administration & dosage* / Q000378:metabolism; D006801:Humans; D007263:Infusions, Parenteral; D007700:Kinetics; D008954:Models, Biological; D012984:Software
D005169:Factor VIII