Abstract
Majority of Pseudomonas aeruginosa strains were inhibited at 25-50μg/ml of carbenicillin. There was no difference in MIC's determined using either MUELLER-HINTON agar or Heart Infusion agar. All strains which showed one plus or more sensitivity in either of mono-or tri-disc test showed MIC of 100μg/ml or less. In view of the high serum concentrations obtainable with 20-30g per day dose of carbenicillin, the disc sensitivity test for this antibiotic should reasonably be interpreted as sensitive when it is one plus or more.
The combination of carbenicillin with gentamicin or dibekacin showed marked synergism in vitro against Pseudomonas aeruginosa.
