1. Patients who have "heartburn" 2 days a week or more during 7 days until the treatment
period (during the observation period).
2. Patients with "heartburn diary" that is completely filled out during 7 days until the
treatment period (during the observation period). If the observation period is 8 days
or longer, those with heartburn diary of which entries are fulfilled 80% or more
during the observation period.
3. Patients with 80% or better drug compliance for antacids during the observation
period.
4. Patients whose percentage of time showing pH<4. 0 (% time pH<4. 0) is not 0%* during the
24-hour esophageal pH monitoring at the end of observation period (at the beginning of
treatment period). *If parameters calculated from analytical program show 0. 0% after
round-off, this patient cannot be entered into the treatment period.
Exclusion Criteria:
Patients who meet any of the following criteria will be excluded from the study.
1. Patients who cannot keep adequate entries of heartburn diary by themselves.
2. Patients who strongly complain "feeling of heavy stomach" and/or "abdominal
bloating."
3. Patients who have a complication or history of psychiatric or psychosomatic disease
(e. g., manic-depressive psychosis, obsessive-compulsive neurosis, or others) or those
who are on an antidepressant or anti-anxiety agent (accepted if only for a hypnotic
treatment).
4. Patients who have undergone Helicobacter pylori eradication therapy, and less than 6
months* have elapsed from the end of H. pylori eradication therapy to the beginning of
the observation period. *: The same day 6 months earlier, and the day at the end of 6
months earlier if it is at the end of month.
5. Patients with open gastric or duodenal ulcer.
6. Patients with acute gastritis.
7. Patients with a history of any surgical intervention that affect peptic secretion
(e. g., upper gastrointestinal tract resection and/or vagotomy).
8. Patients with Barrett's esophagus, esophageal stenosis, or pyloric stenosis.
9. Patients with scleroderma.
10. Patients with a history or complication of angina pectoris.
11. Patients who work at night (working for a night-shift).
12. Patients who received proton pump inhibitors (PPIs) within 3 weeks prior to
pre-observation screening.
13. Patients who need NSAIDs (except topical preparations), steroids (except topical
preparations), and/or aspirin treatment every day.
14. Patients receiving dialysis therapy.
15. Patients with a serious complication such as cardiovascular disease (myocardial
infarction, etc.), hematological disorder (e. g, aplastic anemia), renal disease (e. g.,
acute or chronic renal failure), hepatic disease (e. g., cirrhosis), or malignant
tumor.
16. Patients with known hypersensitivity to antacids or PPIs.
17. Patients who are pregnant or those with childbearing potential, or those who wish to
become pregnant or are lactating during the study period.
18. Patients receiving another investigational drug or those who received another
investigational drug within 6 months prior to pre-observation screening* *:
Registration is allowed on the same day of 6 months earlier, and the day at the end of
6 months earlier if it is at the end of month.
19. Patients who are judged to be ineligible for the study entry by the investigator or
subinvestigator.
