Patient case (clinical description): A 48-year-old man comes to the office complaining of heartburn and acid reflux.  He has taken over-the-counter antacids but sees no relief.  Other medical history is unremarkable.  The patient does not use tobacco, alcohol, or illicit drugs.  Vital signs are within normal limits.  BMI is 31 kg/m2.  Physical examination is  positive for mild tenderness in upper stomach. Chest x-ray shows an air-fluid opacity behind the heart.  A barium swallow study reveals approximately 1/3 of the stomach herniating through the esophageal hiatus.

Patient's own account: I went to my doctor's office because of a non-stop heartburn and some acid reflux. I took over-the-counter medications, but it keeps going strong! I don't smoke, take drugs or drink alcohol, I'm healthy! The doctor took my vitals, which turned out normal. My BMI is 31, which might be a bit too much for a 48-year-old guy like me. They examined my stomach and found a mild tenderness in the upper part. I also did some X-rays, and they found out that I have an air-fluid opacity behind my heart. I did another X-ray, and it turns out that a part of my stomach went up my chest through a hole in my diaphragm!

Clinical trial: Compound Sodium Alginate Oral Suspension Sachet 4-hour Esophageal pH Study in GERD Patients

Eligibility criteria:
Inclusion Criteria:

          -  Primary diagnosis: Current evidence of symptomatic GERD in accord with the Montreal
             definition. Patients should have a GERD history of frequent episodes of GERD-related
             symptoms during at least the last 2 months prior to study screening. The patient must
             also meet the following criteria:

               -  The main symptom is heartburn and/or acid reflux. Symptoms persist or have
                  occurred repeatedly for at least the last 2 months;

               -  The frequency of occurrence of heartburn is ≥ 3 days/week and the score of
                  severity of heartburn in general is moderate or severe within 3 weeks before
                  screening

          -  Patients who are willing to consume the entire standard refluxogenic test meal.

          -  Patients who have a screening 24 h pH monitoring test assessing the percentage of time
             when the pH falls below pH 4 which confirms significant acid reflux of >4.2% over the
             24 h period.

        Exclusion Criteria:

          -  Patients who have a history of drug, solvent or alcohol abuse (weekly alcohol intake ≥
             140g).

          -  Patients who have suffered cardiac chest pain within the last year.

          -  Patients who have suffered a recent, significant unexplained weight loss of more than
             6 kg in the last 6 months.

          -  Female patients of childbearing potential who, for the duration of the study, are
             either unwilling or unable to take adequate contraceptive precautions or are unwilling
             to be sexually abstinent.

          -  Pregnancy or lactating mother.

          -  Patients with a history and/or symptom profile suggestive of the following: any other
             gastrointestinal (GI) disease (e.g. gastric or duodenal erosions and polyps larger
             than 0.5 cm), erosive GERD Los Angeles [LA] classification grades C-D, Barrett's
             esophagus, acute peptic ulcer and/or ulcer complications, Zollinger-Ellison syndrome,
             gastric carcinoma, pyloric stenosis, oesophageal or gastric surgery, intestinal
             obstruction, current pernicious anaemia, hiatal hernias greater than 3 cm, requirement
             for low sodium diet, known gastrointestinal bleeding (hematochezia or hematemesis)
             within the last 3 months, and severe diseases of other major body systems.

          -  Patients who have taken anti-cholinesterase drugs, traditional Chinese medicines for
             treating gastrointestinal disease, sucralfate or misoprostol preparations within 7
             days prior to screening or throughout the study.

          -  Patients who have taken Proton Pump Inhibitors (PPIs) during the 28 days prior to
             screening, prokinetics or H2 antagonists during the 5 days prior to screening, or
             systemic glucocorticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs except
             low dose aspirin given for cardioprotection) on more than 3 consecutive days during
             the last 28 days prior to screening.

          -  Patients who have taken any antacids within 24 hours before screening (Visit 1) and
             throughout the remainder of the study.

          -  Patients taking mucous membrane protection drugs or motility stimulants for 5 days
             prior to screening and throughout the study.

          -  Patients who are vegetarian.

          -  Patients with difficulty in swallowing.

          -  Patients with known hypophosphataemia, phenylketonuria or hypercalcaemia.

          -  Patients who have previously undergone esophageal, gastric or duodenal surgery at any
             time or who have undergone any other major surgery with general anaesthesia within the
             last three months.

          -  Patients with severe constipation, or history of intestinal obstruction.

          -  In the opinion of the Investigator, patients with insufficient heart or kidney
             function and patients who require a low sodium diet.

          -  Patients either with any co-existing condition which, in the opinion of the
             Investigator, would be likely to compromise patient safety or interfere with
             assessment of efficacy; or with any clinically significant abnormal laboratory values.

          -  Patients with impaired renal function or severe renal insufficiency.

          -  Any previous history of allergy or known intolerance to any of the formulation
             constituents

          -  Clinically significant abnormalities in the physical examination, electrocardiogram
             (ECG) and safety analysis.

          -  Patients taking or requiring to take macrolide antibiotics, such as erythromycin,
             azithromycin, from the day before screening.

          -  Previously randomised into the study.

          -  Employee at study site.

          -  Partner or first-degree relative of the Investigator.

          -  Participation in a clinical study in the previous 6 months.

          -  Unable in the opinion of the Investigator to comply fully with the study requirements.
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Years old.
Subject must be at most 65 Years

Eligibility (NLI label): Contradiction