- Twenty four hour intragastric acidity and plasma gastrin concentration in healthy volunteers taking nizatidine 150 mg, nizatidine 300 mg, ranitidine 300 mg, or placebo at 21:00 h. Lanzon-Miller, S., Pounder, R.E., Chronos, N.A., Raymond, F., Hamilton, M.R., Dalgleish, D. Gut (1988)