"been diagnosed with gastritis 7/8 months ago omeprazole not working now on oesmaprole nexium (esomeprazole) past 6wks slight improvement but is this the best one " answered by dr corey clay: scope: time to rule out potential causes for omeprazole resistant hear. Severe acid reflux omeprazole not working. Severe acid reflux omeprazole not working which foods to avoid (