Adaptability of Gonocoecus to Four Bacteriostatic Agents, Sodium Sulfathiazole, Rivanol Lactate, Promin, and Penicillin.

Five strains of the gonococcus were adapted to grow in gradually increased concentrations of each of the following agents: sodium sulfathiazole, rivanol lactate, promin, and penicillin. Only slight adaptation to growth was attained, however, when the strains were exposed to gradually increased concentrations of sodium sulfathiazole, rivanol lactate, and promin in combination. When penicillin was added to the above 3 drugs, none of the 5 strains developed resistance to their combined effects. Interpretation of the results and the possible clinical application of the in vitro observations are presented.