In this sense CPE is low cost, simple to operate and environmentally friendly because uses alternative solvents such as surfactants, lowering the organic solvent consumption.The aim of this work was to develop and validate a methodology based on CPE coupled to ultra-performance liquid chromatography and electrospray tandem mass spectrometry detection (UFLC-MS/MS) for analysis of Abacavir (ABC), Efavirenz (EFV), Lamivudine (3 TC) and Nelfinavir (NFV) in human plasma.