[Clinical effect of nifedipine in patients with achalasia]

The effect of nifedipine, one of calcium antagonists, was studied on esophageal function of 10 patients with achalasia. Lower esophageal sphincter pressure (LESP) was measured with constantly perfused catheter before and after sublingual administration of 10 mg nifedipine. Nifedipine decreased LESP both in achalasia patients and normal controls except one patient. The fall of LESP by nifedipine seems to correlate with initial resting LESP. A clinical trial of nifedipine on patients with achalasia was carried out taking nifedipine sublingually in a daily dosage of 30 to 60 mg before meal. Nifedipine therapy gave good results in 8 patients, and poor response in one and no effects in one patient. Nifedipine improved symptoms of achalasia, but did not improve the degree of esophageal dilatation. Side effect was observed in only one patient, which was flushing of extremities caused by vasodilation, and it is not hazardous to continue nifedipine therapy. Sublingual administration of nifedipine in patients with achalasia is very useful way of medical treatment in two respects, 1) nifedipine decreases LESP, and 2) sublingual administration does not need to pass through the drug through esophagogastric junction which pressure is abnormally high in achalasia patients.