The effect of Iberogast on heartburn in patients with indigestion

INTERVENTION: All patients will receive in one period either a placebo or Iberogast (STW5) (20 drops three times daily) for at least 4 weeks, followed by a second period in which they will receive the other study medication (placebo if they received Iberogast during the first period and Iberogast if they received placebo during the first period). CONDITION: Functional heartburn, Dyspepsia ; ; PRIMARY OUTCOME: ‐ Gastro‐oesophageal reflux disease symptom score improvement based on RDQ Questionnaire score SECONDARY OUTCOME: ‐ Number of gastro‐oesophageal reflux episodes during the 24‐hr study (both mixed/liquid reflux episodes and both acidic and non‐acidic episodes) ; ; ‐ Proportion of acid and non‐acid reflux episodes ; ; ‐ Total acid exposure time during 24‐hour pH‐impedance studies ; ; ‐ Quality of life (using the Quality of life in Reflux and Dyspepsia QoLRaD Questionnaire) ; ; ‐ Oesophageal sensitivity to acid perfusion ; ; Time to symptoms during oesophageal acid exposure ; ; Time to pain during oesophageal acid exposure (if present) ; ; Symptom severity during oesophageal acid exposure (VAS) INCLUSION CRITERIA: ‐ Age above 18 ‐ A history of dyspepsia (according to the Rome IV criteria) with heartburn ‐ Upper gastro‐intestinal causes of the complaints excluded via gastroscopy with in addition an abdominal echography if found to be necessary by the physician