Mezlocillin concentrations in human aqueous humour after intravenous and subconjunctival administration

27 patients received either 4 g intravenous infusion 1-3 h or 100 mg subconjunctival application of mezlocillin 1-12 h before cataract extraction. After intravenous administration the mean aqueous humour concentration of mezlocillin was 2.9 micrograms/ml after 2 h. The subconjunctival dose produced a mean aqueous humour concentration of 23 and 2.6 micrograms/ml after 3 and 12 h, respectively. These levels are above the minimum inhibitory concentration of mezlocillin for sensitive organisms.