title: Oral microflora and selection of resistance after a single dose of amoxicillin.
abstract: The study aimed to determine the effects of a single-dose antibiotic prophylaxis on normal oral microflora. A single dose of 2 g amoxicillin was given to 29 healthy volunteers. Saliva was collected before antibiotic administration (day 1), and again on days 2, 5, 10, 17 and 24 and subjected to culturing and antibiotic sensitivity analysis. Twenty-one per cent (6/29) of the individuals carried penicillin-V- and amoxicillin-resistant viridans streptococci before antibiotic administration. After a single dose of amoxicillin there was a significant reduction in Streptococcus salivarius on days 2 and 5, a significant reduction in other viridans streptococci on day 2 and the proportion of viridans streptococci with reduced susceptibility to amoxicillin was significantly increased on days 2 and 5. A single dose of amoxicillin can cause an ecological disturbance and induce selection of resistant strains in the oral microflora.
authors: Department of Dental Medicine, Division of Periodontology, Karolinska Institutet, Huddinge, Sweden. Electronic address: Dalia.Khalil@ki.se.
authors: D
authors: D
authors: Khalil
authors: Department of Dental Medicine, Division of Periodontology, Karolinska Institutet, Huddinge, Sweden.
authors: M
authors: M
authors: Hultin
authors: Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
authors: M U
authors: MU
authors: Rashid
authors: Department of Dental Medicine, Division of Orofacial Diagnostics and Surgery, Karolinska Institutet, Huddinge, Sweden; Department of Oral and Maxillofacial Surgery, Karolinska University Hospital, Stockholm, Sweden.
authors: B
authors: B
authors: Lund
mesh_terms: D000328:Adult; D000658:Amoxicillin / Q000008:administration & dosage* / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000494:pharmacology; D019072:Antibiotic Prophylaxis; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D012463:Saliva / Q000382:microbiology*; D000070001:Streptococcus salivarius / Q000187:drug effects*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D000658:Amoxicillin
keywords: Antibiotic resistance; Ecological disturbance; Oral microflora; Prophylactic antibiotic use; Selection of resistance