Amoxycillin administered by two dosage regimens

The emergence of antibiotic resistance is a problem in Myanmar nowadays and rational use of antibiotics could help solve this problem. A comparative study of amoxycillin administered by two dosage regimens, 250 mg 6, hourly and500 mg 8 hourly, was performed to explore the clinical significance of differentdosage regimens based on plasma drug concentration achieved. Using a cross-over design, the study was conducted on 22 healthy volunteers, measuring plasma amoxycillin concentration at different times. Plasma amoxycillin concentration in both regimens reached well above the known minimum inhibitory concentration (MIC) of common or gunisms such as alpha & beta hoemolytic streptococci, non-penicillinase producing strains of Staph. aureus, Diplococcus pneumoniae, Haemophilus influenzae, Neisseria gonorrhoeae, Salmonella species and Proteus mirabilis. So bothregimens are appropriate for use in infections by these organisms. For urinary tract infections by Escherichia coli, both dosage regimens may be effective. For systemic infection by E.coli and Shigella species only 500 mg 8 hourly regimen achieved MIC concentration and may be considered more suitable than 250 mg 6 hourly regimen. In case of infections caused by penicillinase producing strains of Staphylococcus aureus, Klebsiella pneumoniae, Enterobacter cloacae and Psudomonasaerugenosa, their MICs higher than the peak plasma drug concentrations were achieved by both dosage regimens. So both regimens are not effective in the treatment of these infections. By assessing peak plasma amoxycillin concentration, it was found that "food disturbs absorption of amoxycillin".