title: Clinical effects of STW 5 (Iberogast) are not based on acceleration of gastric emptying in patients with functional dyspepsia and gastroparesis.
abstract: STW 5, a herbal extract, is effective for the treatment of symptoms in patients with functional dyspepsia (FD). However, its mode of action is still unclear and a modulation of gastric motility is hypothesized. This multicentre, placebo-controlled double-blind study addressed the question of whether STW 5 accelerates gastric emptying in patients with FD and gastroparesis. One-hundred and three patients diagnosed with FD were randomly assigned to a treatment with either STW 5 or a liquid placebo for 28 days. The primary end point of the study was a change of a validated gastrointestinal symptom (GIS) score under treatment. Additionally, patients underwent a (13)C octanoic acid breath test for the assessment of the gastric half-emptying time (t(1/2)). Patients with prolonged t(1/2) were diagnosed with gastroparesis and requested to repeat the test at the end of treatment. A change of t(1/2) was defined a secondary study end point. t(1/2) was prolonged in 48.6% of patients in the STW 5 group and in 43.8% of the placebo group. During treatment, t(1/2) increased non-significantly in patients treated with STW 5 (+23 +/- 109 min; P = 0.51) and slightly accelerated among patients in the placebo arm (-26 +/- 51 min; P = 0.77) (P = 0.49). The improvement of the GIS (P = 0.08) and the proportion of patients with a treatment response (P = 0.03) were more pronounced in the STW 5 group. Our findings suggest that the clinical effects of STW 5 in patients with FD and gastroparesis are not directly mediated by an acceleration of gastric emptying. A clear-cut correlation with symptom improvement is still lacking.
authors.affiliation: Medical Department I, Hospital of the J.W. Goethe-University, Frankfurt, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Braden
authors.forename: W
authors.initials: W
authors.lastname: Caspary
authors.forename: N
authors.initials: N
authors.lastname: Börner
authors.forename: B
authors.initials: B
authors.lastname: Vinson
authors.forename: A R J
authors.initials: AR
authors.lastname: Schneider
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001944:Breath Tests; D002210:Caprylates; D004311:Double-Blind Method; D004415:Dyspepsia / Q000188:drug therapy* / Q000503:physiopathology; D023381:Endpoint Determination; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects*; D005765:Gastrointestinal Agents / Q000627:therapeutic use*; D018589:Gastroparesis / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010936:Plant Extracts / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D002210:Caprylates; D005765:Gastrointestinal Agents; D010936:Plant Extracts; C039964:iberogast; C031492:octanoic acid