title: Double-blind comparison of absorbable colloidal bismuth subcitrate and nonabsorbable bismuth subnitrate in the eradication of Helicobacter pylori and the relief of nonulcer dyspepsia.
abstract: BACKGROUND
  Bismuth is widely used for the eradication of H. pylori, especially in developing countries, although there are concerns over its neurotoxicity. Whether bismuth has to be absorbed in humans to act against H. pylori is not known. In this study, we compared "absorbable" (colloidal bismuth subcitrate) and "nonabsorbable" (bismuth subnitrate) bismuth as part of triple therapy in the eradication of H. pylori.
  
  
  METHODS
  A double-blind, randomized, placebo-controlled trial was carried out with 120 H. pylori-positive patients with nonulcer dyspepsia. Group CBS + Ab (n = 35) received colloidal bismuth subcitrate (one tablet qds), amoxicillin (500 mg qds), and metronidazole (400 mg tds). Group BSN + Ab (n = 35) received bismuth subnitrate (two tablets tds) and the same antibiotics. Group Ab (n = 35) received placebo bismuth (two tablets tds) and the antibiotics. Group BSN (n = 15) received bismuth subnitrate (two tablets tds) and placebo antibiotics. Bismuth was taken for 4 weeks and the antibiotics for the first 2 weeks. H. pylori eradication, side effects, compliance, pre- and post-treatment symptom scores, and bismuth absorption were assessed.
  
  
  RESULTS
  H. pylori eradication was 69%, 83%, 31%, and 0% in CBS + Ab, BSN + Ab, Ab, and BSN, respectively. Side effects, compliance, and symptom relief were similar in all groups, but blood bismuth levels were significantly greater in CBS + Ab than the other three groups.
  
  
  CONCLUSIONS
  The efficacy of bismuth-based therapies as part of triple therapy in the eradication of H. pylori is unrelated to absorption. Hence, the use of effective but poorly absorbed bismuth preparations should be encouraged for bismuth-based eradication therapies.
authors.affiliation: Gastrointestinal Laboratory, The Rayne Institute, St Thomas' Hospital, London, UK.
authors.forename: M W
authors.initials: MW
authors.lastname: Whitehead
authors.forename: R H
authors.initials: RH
authors.lastname: Phillips
authors.forename: C E
authors.initials: CE
authors.lastname: Sieniawska
authors.forename: H T
authors.initials: HT
authors.lastname: Delves
authors.forename: P T
authors.initials: PT
authors.lastname: Seed
authors.forename: R P
authors.initials: RP
authors.lastname: Thompson
authors.forename: J J
authors.initials: JJ
authors.lastname: Powell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001729:Bismuth / Q000009:adverse effects / Q000097:blood / Q000627:therapeutic use*; D004311:Double-Blind Method; D004415:Dyspepsia / Q000097:blood / Q000188:drug therapy* / Q000382:microbiology; D016481:Helicobacter Infections / Q000097:blood / Q000188:drug therapy*; D016480:Helicobacter pylori; D006801:Humans; D007408:Intestinal Absorption; D008875:Middle Aged; D009942:Organometallic Compounds / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D009942:Organometallic Compounds; C010804:bismuth subnitrate; C002791:bismuth tripotassium dicitrate; D001729:Bismuth