Efavirenz pharmacokinetics in cerebrospinal fluid and plasma over a 24-hour dosing interval.
We determined the pharmacokinetics of efavirenz in plasma and cerebrospinal fluid (CSF) over a 24-h dosing interval in a patient who had undergone a lumbar drain because of cryptococcal meningitis. Drug concentrations were determined by high-performance liquid chromatography-tandem mass spectrometry in paired CSF (n = 24) and plasma (n = 25) samples. The median plasma efavirenz concentration was 3,718 ng/ml (range, 2,439 to 4,952), and the median CSF concentration was 16.3 ng/ml (range, 7.3 to 22.3). The CSF/plasma area-under-the-curve ratio was 0.0044 corresponding to a CSF penetration of 0.44% of plasma.
Department of Infectious Diseases, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. firstname.lastname@example.org
SourceAntimicrobial agents and chemotherapy 56:9 2012 Sep pg 4583-5
Area Under Curve
Chromatography, High Pressure Liquid
Tandem Mass Spectrometry
Pub Type(s)Journal Article
Research Support, Non-U.S. Gov't