Medical treatment of esophageal achalasia. Double-blind crossover study with oral nifedipine, verapamil, and placebo.
Calcium channel blockers have been previously shown to decrease lower esophageal sphincter (LES) pressure and improve symptoms in achalasia. We performed a placebo-controlled, double-blind, crossover study to assess the effects of oral nifedipine and verapamil on LES pressure, amplitude of esophageal body contraction, and clinical symptomatology in eight patients with symptomatic achalasia diagnosed by endoscopy, barium swallow, and manometry. Patients were randomized to receive up to 20 mg nifedipine, 160 mg verapamil, or placebo and underwent esophageal manometry before (baseline) and after four weeks on each drug. Diary cards were kept to record and grade symptoms and drug plasma level determinations were correlated with manometric and clinical findings. Both nifedipine and verapamil caused a statistically significant decrease in mean LES pressure, but only nifedipine caused a significant decrease in the amplitude of contractions of the smooth muscle portion of the esophagus. No statistically significant differences in the overall clinical symptomatology were noted with any of the drugs, although some individual improvements in dysphagia and chest pain were noted. We conclude that, despite the reduction in LES pressure and contraction amplitude of the distal esophageal body, oral nifedipine and verapamil do not significantly alter the clinical symptomatology of patients with achalasia.