Plasma concentrations during repeated intravenous and oral methyl-proscillaridin application in man.

The aim of this study was to establish data on the plasma levels of the glycoside derivative methyl-proscillaridin (MP) following repeated intravenous and oral doses. The study was carried out on healthy male volunteers. Each received 0.5 mg of MP daily at 8 a.m. for 7 days. 6 volunteers received the drug i.v., 6 p.o. as tablets and 5 p.o. as elixir. Plasma glycoside concentrations were measured utilizing a 86Rb-erythrocyte assay. The mean plasma concentrations on the 6th and 7th days of application were: 752.9 (Sx = 303.5) pg/ml for the i.v. route, 432.9 (Sx = 115.5) pg/ml for the tablets and 473.1 (Sx = 321.5) pg/ml for the elixir. The mean ratio between plasma concentrations with tablets and i.v. injection averaged 63%. It is concluded that the therapeutic activity of oral MP is about 60 to 70% that of the i.v. application.