Effects of nifedipine in achalasia and in patients with high-amplitude peristaltic esophageal contractions.

We studied the esophageal effects of nifedipine in 20 patients with achalasia (20 mg sublingually) and nine patients with high-amplitude peristaltic esophageal contractions (nutcracker esophagus) (20 mg orally). In patients with achalasia, nifedipine decreased lower esophageal sphincter (LES) pressure by approximately 30%. In ten patients with achalasia, plasma nifedipine concentrations were 45.3 +/- 17.7 and 57.4 +/- 12.8 ng/mL (means +/- SEM) at 30 and 60 minutes, respectively, after drug administration. In patients with nutcracker esophagus, nifedipine decreased LES pressure by approximately 50% and contraction amplitude in the body of the esophagus by approximately 25%. After comparison was made with our previous results in normal subjects, we concluded that (1) nifedipine decreased LES pressure in patients with achalasia to a similar extent to that noted in normal subjects; (2) plasma concentrations measured after 20 mg of nifedipine given sublingually to achalasic patients were similar to those found under similar circumstances in normal subjects; and (3) nifedipine decreased LES pressure and contraction amplitude in patients with nutcracker esophagus to a greater extent than was found in normal subjects. These results suggest that double-blind, placebo-controlled clinical trials of nifedipine in the treatment of achalasia or nutcracker esophagus are indicated.