Antibiotic improve treatment outcome as the combined effect of both antibiotics is better than their individual effect. Methicillin-resistant Staphylococcus aureus infections may be treated with a combination therapy of fusidic acid and rifampicin. Antibiotics used in combination may also be antagonistic and the combined effects of the two antibiotics may be less than if the individual antibiotic was given as part of a monotherapy. For example, chloramphenicol and tetracyclines are antagonists to penicillins and aminoglycosides. However, this can vary depending on the species of bacteria. In general, combinations of a bacteriostatic antibiotic and bactericidal antibiotic are antagonistic. Antibiotics are commonly classified
Antibiotic prophylaxis the preferred drugs for perioperative prophylaxis due to their low toxicity. Parenteral systemic antibiotics seem to be more appropriate than oral or topical antibiotics because the chosen antibiotics must reach high concentrations at all sites of danger. It is well recognized that broad-spectrum antibiotics are more likely to prevent gram-negative sepsis. New data demonstrate that third generation cephalosporins are more effective than first and second generation cephalosporins if all perioperative infectious complications are taken into consideration. Dermatologic surgeons commonly use antibiotic prophylaxis to prevent bacterial endocarditis. Based on previous studies, though, the risk of endocarditis following cutaneous surgery is low