The effect of a new
calcium antagonist,
nifedipine, which has a
spasmolytic activity on smooth muscle cells, was studied on the esophageal function of 20 patients with
achalasia of mild and moderate degree. The study was carried out by using constantly perfused
catheters and recording the pressure variations at the lower esophageal sphincter, before and after
sublingual administration of 10-20 mg of
nifedipine. The
drug significantly decreased the lower esophageal sphincter pressure for more than 1 h. A clinical trial was also carried out by assessing the improvement of symptoms in
achalasia patients taking sublingually a dose of 10-20 mg of
nifedipine before each meal. After 6-18 mo of
nifedipine therapy these patients underwent a placebo treatment, whereas an additional group of 9
achalasia patients was treated first with placebo followed by
nifedipine. The
nifedipine treatment gave excellent or good results in a large majority of patients of both groups. The moderate results were only 5 and the poor responses only 3. The clinical improvement induced by
nifedipine was statistically significant when compared, not only with the pretreatment clinical state, but also with the results of the placebo treatment. No tachyphylaxis and few side effects were seen either during the manometric recordings or the longest periods of
therapy. This study suggests that
nifedipine may be advantageously used in the medical treatment of
achalasia of mild or moderate degree.