コンドロン長期投与による職業性難聴進行防止効果に就いて

　I．緒言

　私は既に外因による聴器障害研究の一端として頭部外傷，音響外傷等の臨床的観察を報告して来たが，今回鉄鋼関係騒音下従業員に対し特殊健康診断を行う機会を得て精密聴力検査を施行した。内10例にコンドロン内服投与を行い約1年を完了して再度検査し得た4例に就いてその難聴防止（進行停止）効果に就いて報告する。

In 4 cases of occupational deafness chond-roitin sulfate was administered by daily dosage of 3 g. once a day for 30 days con-secutively interspaced by a rest period of 10 days. Following such a course of treatment total dosage 819 grams of the drug was given to each patient during the period of 1 year which was tentatively adopted for the period of treatment.

Audiograms were obtained on each indivi-dual before and after the treatment. In 5 ears thus examined no change was seen ; in 3 ears the hearing showed improvement.

From the results it may be said that chondroitin sulfate is instrumental in prevent-ing the progress of occupational deafness.