In Europe, use of potatoes (Solani tuberosi tuberecens) is a traditional remedy for stomach complaints. We performed a pilot study on the effectiveness and tolerability of freshly squeezed potato juice in patients suffering from dyspeptic symptoms. After informed written consent, 44 patients with various dyspeptic symptoms were enrolled, to drink for 1 week twice daily 100ml or more of potato juice (Biotta, if complaints persisted, a further 100ml was recommended. Validated outcome measures included the gastrointestinal symptom (GIS) profile, a disease-specific health assessment questionnaire (QOLRAD) and self-rated treatment success (efficacy, a 5-point Likert Scale). The study was completed by 42 patients. The GIS and QOLRAD scores improved significantly by 41.9+/-40.8% (p=0.001) and 50.7+/-36.1% (p<0.001), respectively (ITT); the absolute values changed from 11.5+/-5.1 to 6.3+/-5.3 (GIS) and 62.0+/-25.7 to 32.0+/-28.8 (QORAD). Sixteen, 18 and 26 patients, respectively, rated the effectiveness of the treatment as very good or good on the GIS, QOLRAD (improvements >60%) and on efficacy, respectively. Poor treatment success was achieved in 13 (GIS), 11 (QOLRAD) and 10 (Efficacy), not necessarily by the same patients. Since about two-thirds of the patients benefited to some extent from the treatment, potato juice in its present formulation may be useful for self-treatment. However, placebo-controlled studies with a longer treatment period are needed to confirm this.