Fenfluramine and idiopathic pain: a serotonergic study in non-psychiatric patients with functional gastrointestinal disorder

Nonulcer dyspepsia. Current concepts and management

NUD is a common heterogeneous condition with a multifactorial cause. NUD is a cause of considerable morbidity with an annual incidence of 8% and similar incidence of spontaneous resolution. Its economic effects are considerable. The estimated annual cost to the community of NUD is $431 per patient for the initial 6 months after diagnosis. The annual Health Maintenance Organization (HMO) expenditure on acid-related disorders in one Northern California HMO was estimated to be $59.4 million, of which NUD represented a significant proportion. The association of H. pylori infection with NUD is controversial. There are strong epidemiologic evidence and supportive pathophysiological mechanisms to implicate H. pylori causally in a subset of cases. Treatment studies are likewise conflicting. Evidence suggests that treatment cannot guarantee improvement in all cases of H. pylori-related NUD but that a subset would benefit with complete symptom resolution in the long term. It is not possible currently to predict which patients would or would not respond to eradication therapy. The strength of evidence is such that empiric eradication therapy, based on noninvasive H. pylori testing, can be advocated in young patients with dyspepsia safely and effectively with resultant financial savings.

Fenfluramine challenge test predicts outcome in pharmacological treatment of patients with functional gastrointestinal disorder

We investigated if response to the fenfluramine challenge test could predict outcome in 47 nonpsychiatric patients with chronic functional gastrointestinal disorder (FGD) treated with mianserin, a drug closely related to mirtazepine, or placebo. Sixty milligrams of fenfluramine was given orally in the morning on nonfasting basis. Serum cortisol (COR) and prolactin (PRL) were analyzed at baseline, and after 120, 180, and 240 minutes. Patients were then randomized into a 7-week double-blind treatment trial with mianserin or placebo. Response to treatment with mianserin (76% vs.18% for placebo) was closely linked to a high increase in PRL and COR following a fenfluramine challenge test (positive predictive power=72%). Adding length of illness history increased both positive and negative predictive power to 92%. Our results indicate that the fenfluramine challenge test may be a potentially useful tool to identify nonpsychiatric subjects with FGD, who will most likely respond to treatment with a combined alpha2 and 5HT-2 and -3 antagonist.