The effect of ranitidine and cisapride on acid reflux and oesophageal motility was investigated in 18 patients with endoscopically verified erosive reflux oesophagitis. Each patient was treated with placebo, ranitidine (150 mg twice daily), and ranitidine (150 mg twice daily) plus cisapride (20 mg twice daily) in a double blind, double dummy, within subject, three way cross over design. Oesophageal acidity and motility were monitored under ambulatory conditions for 24 hours on the fourth day oftreatment, after a wash out period of 10 days during which patients received only antacids for relief of symptoms. Acid reflux was monitored by a pH electrode located 5 cm above the lower oesophageal sphincter. Intraoesophageal pressure was simultaneously recorded from four transducers placed 20, 15, 10, and 5 cm above the lower oesophageal sphincter. Upright reflux was three times higher than supine reflux (median (range) 13-3 (3 7-35 0)% v 3-7 (0-37-6)% of the time with pH<4*0, p<001, n=18). Compared with placebo, ranitidine decreased total reflux (from 10*0 (3.2-32.6)% to 6-4 (1.2-22-9)%, p<001), upright reflux (p<005), supine reflux (p<0001), and postprandial reflux (p<0-01), but did not affect oesophageal motility. The combination of ranitidine with cisapride further diminished the acid reflux found with ranitidine -that is, cisapride led to an additional reduction of total reflux (from 6*4 (1-2-22.9)% to 3-7 (1.0-12.7)%, p<001), supine reflux (p<0.05), and postprandial reflux (p

1. Individual responses to intravenous boli of omeprazole have shown considerable variability. Data on the individual responses to the new omeprazole infusion formulation are lacking. 2. Individual dose‐ responses in the first 24 h of fixed‐dose and pH‐feedback‐controlled infusions of omeprazole were assessed in two randomised, third‐party blinded, cross‐over studies, using two separate groups of eight healthy subjects. In study A, feedback‐controlled infusions of omeprazole (target pH 5, dose range 0‐12 mg h‐1) and fixed‐dose infusions (8 mg h‐ 1) were compared, both with an initial bolus of 80 mg. Omeprazole plasma concentrations were measured. Study B assessed the effect on individual pH‐control of a loading bolus of either 40 mg or 80 mg omeprazole, followed by feedback‐controlled infusions. 3. Study A: the median % time of pH > 5 was 71.2 (total range: 48.9‐83.2) with feedback infusions and 57.9 (28.0‐95.3) with fixed‐dose infusions (P = 0.06). The mean 24 h infusion doses were 173.1 mg (44.5‐253.1) in the feedback group and 192 mg in the fixed‐dose group. The AUC of omeprazole plasma concentrations ranged widely, but correlated with the % time of pH > 5 during fixed‐dose infusions. Study B: initial boli of 40 mg and 80 mg of omeprazole resulted in similar 24 h median % of time with pH > 5, 69.2 (49.9‐78.8) and 69.6 (44.4‐87.7), respectively. Mean omeprazole doses infused by feedback pump were 187.6 mg (83.1‐253.6) after 40 mg boli and 159.9 mg (61.8‐227.0) after 80 mg boli.(ABSTRACT TRUNCATED AT 250 WORDS)