Pipemidic acid is an antibiotic and derivative of piromidic acid .¹It is active against clinical isolates ofE. coli, P. mirabilis, P. inconstans, Shigella, Salmonella, Alcaligenes, andV. parahaemolyticus(MICs = 0.78-100 µg/ml), as well as drug-resistant clinical isolates ofE. coli, P. mirabilis, Klebsiella, andShigella(MICs = 1.56-6.25 µg/ml). Pipemidic acid is protective against systemicS. aureus, E. coli, K. pneumoniae, andP. aeruginosainfections in mice (ED₅₀s = 237.5, 204.1, 28.6, and 99.5 mg/kg, respectively).²It is also protective againstP. aeruginosa-induced pulmonary and dermal infections (ED₅₀s = 81.7 and 173.2 mg/kg, respectively), as well asE. coli, K. pneumoniae, andP. aeruginosaurinary bladder infections (ED₅₀s = 4.8, 11.9, and 30.6 mg/kg, respectively), in mice.

1.Shimizu, Y., Takase, Y., Nakamura, S., et al.Pipemidic acid, a new antibacterial agent active against Pseudomonas aeruginosa: In vitro propertiesAntimicrob. Agents Chemother.8(2)132-138(1975) 2.Shimizu, M., Takdase, Y., Nakamura, S., et al.Pipemidic acid: Its activities against various experimental infectionsAntimicrob. Agents Chemother.9(4)569-574(1976)