We conducted a meta-analysis to determine what factors in treatment regimens for Helicobacter pylori are associated with increased discontinuation rates. Studies were selected from the 1990-1996 MEDLINE data base, and references in published articles and reviews were obtained. Each article was uniformally abstracted for factors that could potentially affect dropout rates. Drug regimens with high numbers of doses per day had highest dropout rates (p=0.0001). The total dropout rate was lowest for regimens containing a proton pump inhibitor (OR = 0.75, CI 0.57, 0.98). The rate was high in regimens containing a bismuth compound due to side effects (OR = 2.79, CI 1.78, 4.36). The main finding was that drug regimens for eradication of H. pylori that have a high number of doses per day result in higher discontinuation rates than regimens with fewer doses per day.