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.