Cerebrospinal fluid concentrations of trimethoprim during oral and parenteral treatment

Penetration of antimicrobials into the central nervous system is dependent upon several factors such as lipid solubiity, protein binding and molecular size. However, the most important factor is meaningeal inflammation. The present study indicates that trimethoprim has the property of excellent penetration into the cerebrospinal fluid (CSF) even in patients with little or no meningeal inflammation. Furthermore, oral trimethoprim administration seems to be quite as good as parenteral at achieving reasonably high CSF-concentrations.