Among patients with idiopathic (of unknown cause) gastroparesis, use of the antidepressant nortriptyline compared with placebo for 15 weeks did not result in improvement in overall symptoms, according to a study appearing in JAMA. Gastroparesis is a disease of the muscles of the stomach or the nerves controlling the muscles that causes the muscles to stop working, which can result in inadequate grinding of food by the stomach and poor emptying of food from the stomach into the intestine.

Gastroparesis remains a challenging syndrome to manage, with few effective treatments and a lack of rigorously controlled trials. One possible approach to treatment is based on the hypothesis that some of the symptoms (e.g., nausea, pain) arise because of changes in certain nerves. Tricyclic antidepressants are a category of drug often used to treat refractory (not yielding readily to treatment) symptoms of nausea, vomiting, and abdominal pain, according to background information in the article.

Henry P. Parkman, M.D., of Temple University, Philadelphia, and colleagues randomized 130 patients with idiopathic gastroparesis to nortriptyline (n = 65) or placebo (n = 65) to determine whether treatment with the tricyclic antidepressant nortriptyline would result in improvement of symptoms. Study drug dose was increased at 3-week intervals. The primary outcome measure was a decrease in the patient's Gastroparesis Cardinal Symptom Index (GCSI) score of at least 50 percent on 2 consecutive visits during 15 weeks of treatment.

The researchers found that the proportion of patients experiencing symptomatic improvement on 2 visits did not differ between the treatment groups: 15 (23 percent) in the nortriptyline group vs. 14 (21 percent) in the placebo group. There were also no treatment group differences in measures of nausea, fullness or early satiety, or bloating. Treatment was stopped more often in the nortriptyline group (29 percent) than in the placebo group (9 percent), but numbers of adverse events were not different.

"Our results raise general doubts about the utility of tricyclic antidepressants in low doses as a strategy for the treatment of idiopathic gastroparesis," the authors conclude.