Antibiotics are commonly used in dental practice. It has been estimated that 10% of all antibiotic prescriptions are related with dental infections. The association amoxicillin-clavulanate was the drug most frequently prescribed by dentists during 2005, at least in the Valencian Community (Spain). The use of antibiotics in dental practice is characterized by empirical prescription based on clinical and bacteriological epidemiological factors, with the use of broad spectrum antibiotics for short periods of time, and the application of a very narrow range of antibiotics. The simultaneous prescription of nonsteroidal antiinflammatory drugs (NSAIDs) can modify the bioavailability of the antibiotic. In turn, an increased number of bacterial strains resistant to conventional antibiotics are found in the oral cavity. Antibiotics are indicated for the treatment of odontogenic infections, oral non-odontogenic infections, as prophylaxis against focal infection, and as prophylaxis against local infection and spread to neighboring tissues and organs. Pregnancy, kidney failure and liver failure are situations requiring special caution on the part of the clinician when indicating antibiotic treatment. The present study attempts to contribute to rational antibiotic use, with a review of the general characteristics of these drugs.