Pharmacokinetics of quinine in chronic liver disease

The pharmacokinetics of quinine were investigated in a) six healthy male Thai subjects, and b) nine male Thai patients with a moderate degree of chronic liver disease, after a single oral dose of 600 mg quinine sulphate. tmax and t1/2.2 were significantly prolonged in patients (median [range] tmax 2 [1-5] vs 1.6 [0.8-2] h; t1/2,z 23.4 [17.4-41.7] vs 9.7 [7.8-17.2] h), and Vz/F was significantly larger (median [range] 4.21 [2.33-15.87] vs 2.78 [1.49-3.38] 1 kg-1). Median (range) concentration of the plasma unbound Qn fraction collected from the patients at 4 h after drug administration was 17 (8.4-17.8)% of total drug concentration.