Some common characteristics that distinguish antibiotic use in Latin America are a high incidence of infections that are treatable with antibiotics, extensive use and frequent misuse of antibiotics, and frequent self-medication and nonprofessional prescription in the outpatient setting. Community-acquired organisms are generally more antibiotic-resistant in Latin America than in more-industrialized countries. Antibiotics also are used extensively in hospitals, largely for surgical prophylaxis and for nosocomial infections, which occur more frequently (in 15%-20%) in hospitalized patients. Prophylactic use of antibiotics is largely inappropriate--i.e., indiscriminate, inopportune, and prolonged. A frequent outcome of this inappropriate use is the occurrence of nosocomial infections due to strains that are much more drug resistant than those encountered in industrialized countries. The great number of pharmaceutical products available, and the lack of stringent policies regarding drug sales and advertising often result in pressure to prescribe and in confusion not only among the public at large but among physicians themselves. Coordinated efforts to educate health care professionals, campaigns against self-medication, stricter rules for drug sales and advertising, and restricted use of certain antibiotics in hospitals may contribute to rational antibiotic use.