A comparison of omeprazole with ranitidine for ulcers associated with nonsteroidal antiinflammatory drugs. Acid Suppression Trial: Ranitidine versus Omeprazole for NSAID-associated Ulcer Treatment (ASTRONAUT) Study Group

N Engl J Med. 1998 Mar 12;338(11):719-26. doi: 10.1056/NEJM199803123381104.


Background: Suppressing acid secretion is thought o reduce the risk of ulcers associated with regular use of nonsteroidal antiinflammatory drugs (NSAIDs), but the best means of accomplishing this is uncertain.

Methods: We studied 541 patients who required continuous treatment with NSAIDs and who had ulcers or more than 10 erosions in either the stomach or duodenum. Patients were randomly assigned to double-blind treatment with omeprazole, 20 mg or 40 mg orally per day, or ranitidine, 150 mg orally twice a day, for four or eight weeks, depending on when treatment was successful (defined as the resolution of ulcer and the presence of fewer than five erosions in the stomach, and fewer than five erosions in the duodenum, and not more than mild dyspepsia). We randomly assigned 432 patients in whom treatment was successful to maintenance treatment with either 20 mg of omeprazole per day or 150 mg of ranitidine twice a day for six months.

Results: At eight weeks, treatment was successful in 80 percent (140 of 174) of the patients in the group given 20 mg of omeprazole per day, 79 percent (148 of 187) of those given 40 mg of omeprazole per day, and 63 percent (110 of 174) of those given ranitidine (P<0.001 for the comparison with 20 mg of omeprazole and P=0.001 for the comparison with 40 mg of omeprazole). The rates of healing of all types of lesions were higher with omeprazole than with ranitidine. During maintenance therapy, the estimated proportion of patients in remission at the end of six months was 72 percent in the omeprazole group and 59 percent in the ranitidine group. The rates of adverse events were similar between groups during both phases. Both medications were well tolerated.

Conclusions: In patients with regular use of NSAIDs, omeprazole healed and prevented ulcers more effectively than did ranitidine.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects*
  • Anti-Ulcer Agents / adverse effects
  • Anti-Ulcer Agents / therapeutic use*
  • Double-Blind Method
  • Duodenal Ulcer / chemically induced
  • Duodenal Ulcer / drug therapy*
  • Female
  • Histamine H2 Antagonists / adverse effects
  • Histamine H2 Antagonists / therapeutic use
  • Humans
  • Male
  • Middle Aged
  • Omeprazole / adverse effects
  • Omeprazole / therapeutic use*
  • Prognosis
  • Proton Pump Inhibitors
  • Ranitidine / adverse effects
  • Ranitidine / therapeutic use*
  • Remission Induction
  • Stomach Ulcer / chemically induced
  • Stomach Ulcer / drug therapy*


  • Anti-Inflammatory Agents, Non-Steroidal
  • Anti-Ulcer Agents
  • Histamine H2 Antagonists
  • Proton Pump Inhibitors
  • Ranitidine
  • Omeprazole