Pipemidic acid (PPA), a newly synthesized piromidic acid derivative, was examined on its antibacterial activity and absorption after oral administration. Some clinical trials were also carried out.
1) Tests on the sensitivity of clinical isolates revealed that the sensitivity of E. coli strains to PPA was higher than that to NA and PA, and the sensitivity of Klebsiella and Proteus strains to PPA mostly resembled that to NA.
2) Blood levels of PPA in human adults administered 1 g PPA per os showed a peak (7.2-7.5μg/ml) at 1 hour after administration.
3) The rate of urinary recovery was 23. 6-43. 8% within 6 hours.
4) PPA was used in 8 cases with respiratory-or urinary-tract infections. Favourable results were obtained in 5 of the cases.
5) No side effects were observed in all patients treated with the drug except one who complained nausea after administration, but it was obscure if the nausea of this patient was attributable to the drug or not, because drugs for hypertention were simultaneously given.
