title: [Effect of vitamin C administration on gastric colonization by Helicobacter pylori].
abstract: BACKGROUND
  The conventional treatment of Helicobacter pylori infection consists on antibiotics, to which a small but significant number of patients are non-responders. Alternative treatments to the infection have been suggested, including the use of antioxidants. There has been such increasing interest upon vitamin C since it was demonstrated vitamin C concentrations in the stomach of infected patients are significant lower compared to healthy subjects. Pharmacological doses of vitamin C have been investigated for eradication of H. pylori, with controversial results.
  
  
  OBJECTIVE
  To evaluate the effect of oral administration of vitamin C on H. pylori colonization in the stomach of patients with chronic gastritis and patients with peptic ulcer who had experienced antimicrobial treatment failures.
  
  
  METHODS
  Protocol I: randomized, double-blinded, placebo controlled study, with patients with chronic gastritis, with no previous treatment for eradication. Protocol II: open, uncontrolled study, with patients with peptic ulcer, with at least two previous treatments for eradication. Treatment consisted of 5 g vitamin C for 28 consecutive days. The effect of the treatment was evaluated by 14C-urea breath test concerning eradication rate, radioactivity variation and infection suppression.
  
  
  RESULTS
  In Protocol I, 38 patients completed the study--21 received vitamin C and 17 received placebo 28 consecutive days. Eradication rates per-protocol analysis with vitamin C were 0, with 95% confidence interval of 0-15%. In Protocol II, eight patients completed treatment. Eradication rate was 0%, with 95% confidence interval of 0-12%. H. pylori load was not decreased.
  
  
  CONCLUSIONS
  Administration of vitamin C, in a 5 g/day dosage during 28 days is neither effective for H. pylori eradication nor quantitatively alters the bacteria load in the stomach of infected patients.
authors.affiliation: Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP. maykamiji@hotmail.com
authors.forename: Mayra Mayumi
authors.initials: MM
authors.lastname: Kamiji
authors.forename: Ricardo Brandt de
authors.initials: RB
authors.lastname: Oliveira
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D002908:Chronic Disease; D004311:Double-Blind Method; D005260:Female; D005756:Gastritis / Q000188:drug therapy / Q000382:microbiology*; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000188:drug therapy / Q000382:microbiology*; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D001205:Ascorbic Acid