We report label-free quantification of xenobiotic metabolizing enzymes (XME), transporters, redox enzymes, proteases, nucleases and tight junction proteins in 22 human brain microvessel samples. More than 3500 proteins were identified and quantified. These data can be used in physiologically based pharmacokinetic models to predict drug disposition in the brain and permitting dose adjustment (precision dosing) in special populations of patients, such as those with dementia.