OUTLINE: All patients are treated on Regimen A; those receiving tetracycline on Regimen A are switched to Regimen B for their second course; those receiving amoxicillin for their first course receive tetracycline for their second course. Regimen A: Antibiotic Therapy with Gastric Acid Inhibition. Amoxicillin (or Tetracycline in penicillin-allergic patients); Clarithromycin; with Bismuth Subsalicylate; Omeprazole. Regimen B: Antibiotic Therapy with Gastric Acid Inhibition. Tetracycline; Metronidazole, METRO, NSC-50364; with Bismuth Subsalicylate; Omeprazole.