Conventional dose of omeprazole alters gastric flora

Dig Dis Sci. 1995 Sep;40(9):2070-3. doi: 10.1007/BF02208680.


Quantitative cultures were carried out on samples from gastric juice obtained from 12 ambulatory patients with esophagitis before and one month after omeprazole therapy. An increase in the number of patients in whom gastric juice was culture-positive, as well as an increment in the bacterial counts were noted. The spectrum of microorganisms isolated from gastric juice was identical to the normal flora of the oral cavity, mainly alpha-hemolytic streptococci, corynebacteria, and Candida species. Thus, the counts of organisms within gastric contents are simply a reflection of swallowed oral microflora that were able to survive due to the less acidic environment.

MeSH terms

  • Antacids / administration & dosage
  • Antacids / pharmacology*
  • Candida albicans / isolation & purification
  • Corynebacterium / isolation & purification
  • Enterobacteriaceae / isolation & purification
  • Esophagitis, Peptic / drug therapy*
  • Esophagitis, Peptic / microbiology
  • Female
  • Gastric Juice / microbiology*
  • Humans
  • Male
  • Middle Aged
  • Omeprazole / administration & dosage
  • Omeprazole / pharmacology*
  • Stomach / microbiology*
  • Streptococcus / isolation & purification
  • Time Factors


  • Antacids
  • Omeprazole