Antibiotics are antibacterial medicines belonging to the group of antimicrobial chemotherapy drugs. Dentists use them often as common therapeutical agents. Due to the presence of pathogens resistant to their activity, it is important to know the properties, mechanisms of action, indications, and side effects of antibiotic use, which are described in detail in this master thesis. Dental medicine uses antibiotics from the group of penicillin antibiotics, tetracyclines, macrolides, linkozamides, fluoroquinolones, and metronidazole, which belongs to the amebicide group. They are prescribed as therapeutical and prophylactic agents, ingested orally, intravenuously, intramuscularly, or applied topically on the mucous membrane of the oral cavity. Amoxicilin belongs to the group of penicillin antibiotics and it has a devastating effect on the bacterial cell wall. It has a wide range of applications and due to the presence of bacterial resistance, it is often administered in combination with clavulanic acid. Amoxicilin is a medicine of choice for dental infections and is prescribed empirically if a patient is not penicillin-sensitive. Doxycycline is tetracycline and it acts to inhibit the synthesis of bacterial proteins by binding to the bacterial ribosomal subunits. It has a wide range of applications and is most often used in the presence of bacterial resistance in patients with periodontal diseases. Erythromycin and azithromycin are macrolides with broad spectrum of use preventing the synthesis of bacterial proteins by linking to a large ribosomal subunit of bacteria. Klindamycin belongs to the group of linkosamides, it has a wide spectrum of use and the same mechanism of action as the macrolides described above. It is prescribed empirically in the case of penicillin-sensitive patients and is successful in treating bone infections. Ciprofloxacin is a fluoroquinolone that acts on bacteria by preventing the replication of their deoxyribonuclease and is the most effective medicine in periodontal diseases caused by the Agregatibacter acetinomicetemcomitans bacteria. Metronidazole acts on anaerobic bacteria by inhibiting nucleotide synthesis. Metronidazole and penicillin antibiotics are bactericidal while macrolides and tetracyclines are bacteriostats.