Treatment of infections caused by drug-sensitive pathogens in cases where the benefit of such treatment outweighs the potential risk; the question is whether one single antibacterial agent should be used. Infections of ENT-organs and respiratory tract: acute and chronic bronchitis, bronchiectasis, pneumonia (including caused by Pneumocystis carini), pharyngitis, angina (for infections caused by β-hemolytic streptococci of group A, frequency of eradication, non-eradication, otitis. Kidney and urinary tract infections: acute and chronic cystitis, pyelonephritis, urethritis, prostatitis, mild chancre. Digestive tract infections: typhoid and paratyphoid, shigellosis (caused by sensitive strains of Shigella flexneri and Shigella sonnei, if antibacterial therapy is shown), “traveler” diarrhea caused by enterotoxic Escherichia coli strains, cholera (doping). Other bacterial infections: acute and chronic osteomyelitis, brucellosis, nocardiosis, actinomycosis, toxoplasmosis, South American blastomycosis.