Determination of antipsychotic drugs in nails and hair by liquid chromatography tandem mass spectrometry and evaluation of their incorporation into keratinized matrices.

•LC–MS/MS method for detection of 5 antipsychotic drugs in nail and hair samples.•Methodology was fully validated, with LOQs ranging from 10−20 pg/mg.•Concentrations in paired fingernail, toenail and hair samples were compared.•Higher concentrations in hair, and variable results between finger- and toenails.