Modern, intelligent microbes are unusually adaptable to drug treatments. Their ability to communicate at a distance and in close contact helps them fight antibiotics.
Our microbes communicate with each other regardless of how closely we communicate: coughed, sneezed, shook hands, collided in the subway, etc. Having greatly exaggerated the situation, we can say that if a person, A, unreasonably drank an antibiotic, then because of this, the treatment of person B with the same drug may be unsuccessful.
This is now one of the main problems with antibiotic use. The World Health Organization views resistance to them as a more serious threat to humanity than SARS and avian influenza. Indeed, in hospitals, with severe infections caused by resistant microbes, people regularly die in quantities much larger than from SARS. It is worth remembering the problem of the resistance of the tuberculosis pathogen.
In everyday life, with or without reason, take biseptol, tetracycline, erythromycin, penicillin. The problem of professionals is that for a significant part of serious diseases, surgeons use longer than necessary courses of antibiotic therapy, and they also like to prescribe them for preventive purposes. Until now, it has not been possible to convince surgeons to reduce unjustified prescriptions, and this entails unreasonable financial costs and, again, pours water on the mill for the formation of resistance and launches a new round of evolution of intelligent microbes.