title: Antibiotics increase functional abdominal symptoms.
abstract: OBJECTIVE
  Data suggest that subjects with irritable bowel syndrome are more likely to report a recent course of antibiotics. This study tests the hypothesis that a course of antibiotics is a risk factor for an increase in the number of functional bowel complaints over a 4-month period in a general population sample.
  
  
  METHODS
  We initiated a prospective case-control study in three general practices in South London. Consecutive patients aged 16-49 attending their general practitioner with non-GI complaints and given a prescription for antibiotics were invited to participate. Comparison subjects who had not had antibiotics for 1 yr were identified from the practice records by age group, gender, and previous general practitioner visits. Fifty-eight antibiotic and 65 control patients agreed to participate. Questionnaires covering demographic, GI, and psychological data were sent at recruitment and at 4 months. Seventy-four percent of subjects completed the study. The number of symptoms at follow-up compared to that at recruitment.
  
  
  RESULTS
  Twenty of 42 antibiotic subjects (48%) versus 11/49 control subjects (22%) demonstrated one or more additional functional bowel symptoms at 4 months (unadjusted odds ratio = 3.14 [1.27-7.75]) (chi2 = 6.4, p = 0.01). Ten of 42 antibiotic subjects (24%) versus 3/49 control subjects (6%) demonstrated two or more additional functional bowel symptoms at 4 months (unadjusted odds ratio = 4.79 [1.22-18.80]) (chi2 = 5.8, p = 0.02).
  
  
  CONCLUSIONS
  Functional bowel symptoms come and go, but subjects who are given a course of antibiotics are more than three times as likely to report more bowel symptoms 4 months later than controls.
authors.affiliation: Department of General Practice and Primary Care, St George's Hospital Medical School, London, United Kingdom.
authors.forename: P R
authors.initials: PR
authors.lastname: Maxwell
authors.forename: E
authors.initials: E
authors.lastname: Rink
authors.forename: D
authors.initials: D
authors.lastname: Kumar
authors.forename: M A
authors.initials: MA
authors.lastname: Mendall
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects*; D016022:Case-Control Studies; D015331:Cohort Studies; D003967:Diarrhea / Q000139:chemically induced* / Q000453:epidemiology; D005260:Female; D005753:Gastric Mucosa / Q000187:drug effects; D005759:Gastroenteritis / Q000139:chemically induced / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007413:Intestinal Mucosa / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values; D012307:Risk Factors; D018709:Statistics, Nonparametric
chemical_list: D000900:Anti-Bacterial Agents