Nalidixic Acid Indications Nalidex is indicated in the treatment of urinary tract infection caused by susceptible Gram-negative organisms, including Proteus species, Klebsiella species, Enterobacter species and Escherichia coli. Pharmacology Nalidixic acid is a synthetic narrow spectrum antibacterial. It is bacteriostatic or bactericidal depending on the concentration. Nalidixic acid appears to act by inhibiting bacterial DNA […]