Use of isosorbide dinitrate for the symptomatic treatment of patients with Chagas' disease achalasia. A double-blind, crossover trial.

1. A randomized, double-blind, placebo-controlled trial was carried out to determine the efficacy of isosorbide dinitrate (ISD) on dysphagia in patients with Chagasic achalasia. 2. Twenty-three patients with Chagas' disease and dysphagia entered the study and 20 (87%) completed the two 7-day treatment periods. Subjects were given either 5 mg ISD (12 patients) or placebo (11 patients) by the sublingual route for the first 7 days. On the 8th day, patients crossed over and began another 7-day period during which they received the opposite, identical-appearing tablets. 3. Scores attributed by uninformed investigators for the frequency and severity of dysphagia were significantly lower (P less than 0.05) following ISD treatment than after the placebo period or for the pretreatment condition. A significantly higher degree of improvement of dysphagia was experienced by the patients during ISD treatment than during the placebo period. Fourteen patients experienced meal-related headaches during ISD, but not placebo treatment. The extent of improvement in general well-being due to ISD was the same when the drug was given in the first or second test period. 4. Our results indicate that ISD, 5 mg by the sublingual route, is effective in alleviating dysphagia in patients with Chagasic achalasia but its usefulness is limited by the high rate of headache as a side effect.