Antibiotic antibiotic therapy. The antibiotic treatment may select for bacterial strains with physiologically or genetically enhanced capacity to survive high doses of antibiotics. Under certain conditions, it may result in preferential growth of resistant bacteria, while growth of susceptible bacteria is inhibited by the drug. For example, antibacterial selection for strains having previously acquired antibacterial-resistance genes was demonstrated in 1943 by the Luria–Delbrück experiment. Antibiotics such as penicillin and erythromycin, which used to have a high efficacy against many bacterial species and strains, have become less effective, due to the increased resistance of many bacterial strains. Resistance may take the form
Antibiotic use in dentistry prophylaxis to prevent post-operative infections, resulting from bacteraemia, and infective endocarditis was practiced by dentists, especially in patients at high risk (i.e. with heart problems). However, according to new recommendations from the National Institution for Health and Care Excellence (NICE), antibiotic prophylaxis should not be offered for all patients at risk of infective endocarditis. This is due to the ever-increasing antibiotic resistance and there is no or very little evidence to show whether antibiotic prophylaxis is effective or ineffective against post-operative infections. Moreover, it is yet to be established whether the benefits of administering antibiotics prophylactically outweighs the inherent risks,