A method has been developed for the simultaneous extraction and determination of five of the most commonly used anticoccidial drugs (nicarbazin, lasalocid, monensin, narasin and salinomycin) from livers and eggs by LC-MS-MS. Results show good repeatability, with mean spiked recoveries for nicarbazin, lasalocid, monensin, narasin and salinomycin in poultry livers in the average range of 92-118%, and 86-110% in eggs. The detection limit is at 1 ng ml(-1) for all the named compounds and a quantitation level of 2.5 ng g(-1) has been achieved. A high throughput of samples is achievable using this method which allows the analysis of up to 40 samples by one analyst in a day.