<p>　Sublingual immunotherapy with tablets for the treatment of Japanese cedar pollinosis currently does not have any age restrictions. Until May 2018, the treatment was administered as a liquid preparation, and the indication was for individuals who were 12 years or older. Previous reports on sublingual immunotherapy have not sufficiently examined medication adherence, clinical effects, and side reactions in children and adults. Using the results of a questionnaire that was previously used in past surveys, we have newly analyzed the statistical differences in clinically important factors such as pediatric and adult medication adherence, clinical effects, and side reactions. These results are reported along with a review of the literature. The subjects were 1017 patients with Japanese cedar pollinosis who started sublingual immunotherapy between 2014 and 2018 and were continuing to receive this treatment. The age distribution ranged from 12 to 79 years. Most of the subjects were in their 40s, followed by those in their 10s. At the start of the survey, subjects under the age of 15 years were classified as children and those over the age of 15 years were classified as adults. We distributed a self-written questionnaire at the end of each pollen dispersal season. The survey items included adherence to medication for children and adults, the burden of daily sublingual administration, sex (specific effects of sublingual immunotherapy according to sex), and the duration of illness as adjustment items, as well as the use of concomitant drugs and side reactions. A multiple logistic regression analysis was performed with adjustments for sex, duration of illness, and medication adherence to examine overall treatment satisfaction. The results showed no statistically significant differences between children and adults for all seasons that were analyzed (multiple logistic regression analysis). In other words, sublingual immunotherapy for Japanese cedar pollinosis had the same effect in children as it did in adults.</p><p>　This study indicated that sublingual immunotherapy was highly safe and satisfying even in children, and no differences in therapeutic effect were seen between children and adults. In addition, this study showed that relatively mild side reactions appeared during the first season, especially among women. Further analysis of the differences between children and adults regarding how long the therapeutic effect will persist after the end of a 3-to-5-year treatment period is needed.</p>