Background and Aims: Gastric sensation and accommodation are best studied using a barostat but the cumbersome, invasive nature of this method limits applicability. The drink test was developed as a noninavasive test of gastric capacity that provides information similar to that obtained by barostat testing. The present study investigated the relationship between drink test, gastric function, symptom severity and psychiatric distress.Methods: Seventy-three healthy subjects and 92 subjects meeting Rome II criteria for functional dyspepsia were evaluated. All participants were H. pylori negative. Subjects were evaluated with a 5-minute water load test, ¹³C-Spirulina platensis gastric emptying breath test and electrogastrography. Symptoms, quality of life and psychiatric distress were measured by Nepean Dyspepsia Index, Psychological General Well Being Index, SF-36 and SCL-90. A subset of controls underwent either test-retest drink test or comparison of 100ml/min water-based drink test with the 5-minute water load and a caloric-based 5-minute drink test. An additional subset of controls, dyspeptics and patients with diabetic or idiopathic gastroparesis estimated drinking capacity prior to 5-minute water load test using a 100mm visual analog scale. Results: The 5-minute water load correlated well with the 100ml/min drink test (r=0.7929) but not the caloric-based test (r=0.1995). Males drank significantly more than females and the volume to fullness was positively correlated with height and increasing age but not BMI. Drinking capacity was significantly less in dyspeptics than controls and abnormal drink tests were seen in 46% of dyspeptics. In dyspeptics, volume to satiety was inversely correlated with symptom severity (r=-0.29; p=0.0154) but not with quality of life or overall psychiatric distress and water load produced more symptoms in dyspeptics, particularly nausea. Gastric neuromuscular function was not different between dyspeptics with normal or abnormal drinking capacity with the exception of EGG which was more likely to be abnormal in dyspeptics with normal drinking capacity. Symptom severity and psychiatric distress was similar between the normal and abnormal drinking capacity groups but the abnormal drinking capacity group reported significantly greater impairment in quality of life. Controls and gastroparetics displayed good correlation between estimated and ingested volumes whereas dyspeptics did not. Conclusions: The 5-minute water load is reproducible and abnormal in almost half of functional dyspeptics. Compared with dyspeptics with normal drinking capacity, dyspeptics with impaired drinking capacity have normal gastric emptying tests and electrogastrograms and similar symptom severity but greater impairment in quality of life. Additionally, compared with controls and gastroparetics, dyspeptics are significantly less able to predict drinking capacity. These data suggest that the drink test identifies a subset of dyspeptics with intact gastric function and abnormalities of visceral perception.