one hundred and ninety duodenal ulcer patients who had relief of pain and endoscopically proven ulcer healing after a short treatment period are allocated at random to double-blind maintenance treatment with a synthetic dehydroprostaglandin-e1 , rioprostil , 300 micrograms , or ranitidine , 150 mg , at bedtime for 6 months .
C0013295
duodenal ulcer
C0034665
ranitidine