Abstract
The fundamental and clinical studies, in the pediatric field, of a broad spectrum semi-synthetic penicillin, aminocyclohexyl penicillin (AC-PC), have been conducted.
(1)In vitro antibacterial activities: The sensitivity of coagulase-positive Staph. aureus isolated from clinical materials was distributed widely, giving a peak at 12.5mcg/ml of AC-PC. In comparison with aminobenzyl penicillin (AB-PC), the in vitro activity of AC-PC against penicillin G-resistant Staph. aureuswas superior to AB-PC, while against the sensitive strains their relation was reversed. Against E. coli and Proteus vulgaris AC-PC exhibited growth inhibition, but was inferior to AB-PC.
(2) Absorption and excretion: The maximum serum levels, when AC-PC was orally given in asingle of 500 or 250mg, reached 9.1 and 4.3mcg/ml in average, respectively. In the fasted subject the peak level was attained at an hour after administration, while it tended to lag somewhat when antibiotic was given after meal. The antibiotic was excreted rapidly, and therefore, persistance in blood was considerably of short duration and it was not detected at six hours after the administration, during which 80% of AC-PC was recovered in urine.
(3) Clinical effects: Of the total of 33 patients (acute tonsillitis 8, acute pharyngitis 4, acute bronchitis 3, acute dyspepsia 9, acute enteritis 6, acute cystitis 2 and pyelonephritis 1), 5 cases showed excellent results, 20 cases good and 8 cases poor. From the results, AC-PC may be more effective against respiratory diseases than the intestinal. As for the dosage in children 50-100mg/kg/day of AC-PC is recommendable.
