To test these hypotheses we will randomly assign 125 Helicobacter pylori-infected children (3 to 10 years of age) into each of the following four groups: Helicobacter pylori eradication treatment, iron supplementation, Helicobacter pylori eradication plus iron supplementation, or placebo. We plan to recruit infected children through a household survey in El Paso, screen their Helicobacter pylori infection status by a stool test, and invite their parents to undergo a confirmatory breath test. Infected children randomly allocated to those four arms of the study will be followed closely during the 6 weeks they are taking the study medication to record any adverse event, followed by a visit at 45 days after treatment to tell whether or not those receiving the medication had their infection eradicated, between 6 and 12 months for hematological evaluation to compare with the baseline levels of iron stores.