Methicillin penetration into the cerebrospinal fluid of patients

Penetration of methicillin through the blood-liquor barrier in neurosurgical patients was studied. When administered in a dose of 2 gm the drug penetrated through the barrier in 1/3 of all observations within 1 to 3 hours. Increased liquor pressure in the patients resulted in prolongation of the antibiotic effect in the cerebrospinal fluid. The methicillin levels in the liquor were no sufficient for the growth inhibition of most methicillin sensitive staphylococci.