We present fast LC-MS-MS analyses of multicomponent mixtures containing flavones, sulfonamides, benzodiazepines and tricyclic amines. Using a short microbore HPLC column with small particle size, five to eight compounds were partially resolved within 15 to 30 s. TurboIonSpray and atmospheric pressure chemical ionization interfaces were well suited to tolerate the higher eluent flow-rates of 1.2 to 2 ml/min. The methods were applied to biological sample matrices after clean-up using solid-phase or liquid-liquid extraction. Good precision and accuracy (average 8.9 and 97.7%, respectively) were achieved for the determination of tricyclic amines in human plasma. Benzodiazepines were determined in human urine with average precision of 9% and average accuracy of 95% for intra- and inter-assay. Detection limits in the low ng/ml range were obtained. An example for 240 injections per hour of demonstrated the feasibility of rapid LC-MS-MS analysis.